What you're feeling now is completely normal, especially since the job involves new skills which you currently do not have.
But have you asked yourself: What're you losing out if you played it safe and passed on this job?
An Alternative Way Of Looking At Things
Considering that the company offered you the job - and I'm guessing probably without having to test your proficiency in the platforms or tech that you mentioned - I presume that your role is not as expertise heavy from the onset as you might think.
Unless you somehow managed to get a job as a brain surgeon without a valid medical degree or experience, then you're REALLY out of your depth here and that company or hospital is obviously not going to do very well.
But I digress.
Even if the job does involve tech or platforms which you do not have any experience with, the company probably believes that with OJT (On the Job Training), you'll be able to pick it up.
I'm also guessing that they're banking on your projected "confidence and competence" to tackle this role head-on and believe that you'll be able to handle it. Perhaps they saw something in your previous experience, where you had to take on something completely foreign and managed to do it well?
Remember: we all have transferable skills, so give yourself a little credit here.
In the worse case scenario where the company and you have mismatched expectations with regard to your capabilities. Then there're two ways to approach this.
Option 1: Forget Everything And Run
Admit that you're lacking the relevant skills and give up.
Option 2: Face Everything And Rise
Admit that you're lacking the relevant skills and show the company that hired you, that you're working on it, and you're on your way to becoming "Employee of the Month" for 3,576 consecutive months.
Speaking from personal experience, I always pick Option 2 because it's way more rewarding.
So What's The Next Step Moving Forward?
1) Go online and start reading everything you can about the platform or skills you need to familiarise yourself with.
Join forums and online groups, and seek out subject matter experts to gain insights into what you're going to get yourself into.
In this day and age, you can pretty much learn anything from YouTube, Reddit, Twitter etc. if you're resourceful enough.
2) If there's a dearth of knowledge online, start looking and going for classes or workshops to pick up the skills you need for your job.
Better still, talk to your managers or hiring manager to see if there're company-identified courses for the job that you've been offered. If you're really lucky, they'll even pay for you to upgrade yourself.
3) Reach out to peers in the same industry or company and find out what are their go-to sources of info. Or simply to tap on their experience. Learn from their mistakes and level up faster.
Attitude Always Counts
Skills can always be picked up and platforms can be learnt. But a person with the right attitude and thirst for self-improvement is someone whom companies would kill to hire.
Since you like the job enough to even interview for it, and the company's willing to take a chance on you, why not do the best you can and see how far you can grow as a person and as an employee?
At the risk of sounding cliche, here's a quote from YouTuber Casey Neistat that really speaks to me when I face situations like yours, "The most dangerous thing you can do in life, is play it safe."
If the company is willing to take a chance on you, don't you think you owe it to yourself to take a calculated leap of faith and show them what you can do?
What you're feeling now is completely normal, especially since the job involves new skills which you currently do not have.
But have you asked yourself: What're you losing out if you played it safe and passed on this job?
An Alternative Way Of Looking At Things
Considering that the company offered you the job - and I'm guessing probably without having to test your proficiency in the platforms or tech that you mentioned - I presume that your role is not as expertise heavy from the onset as you might think.
Unless you somehow managed to get a job as a brain surgeon without a valid medical degree or experience, then you're REALLY out of your depth here and that company or hospital is obviously not going to do very well.
But I digress.
Even if the job does involve tech or platforms which you do not have any experience with, the company probably believes that with OJT (On the Job Training), you'll be able to pick it up.
I'm also guessing that they're banking on your projected "confidence and competence" to tackle this role head-on and believe that you'll be able to handle it. Perhaps they saw something in your previous experience, where you had to take on something completely foreign and managed to do it well?
Remember: we all have transferable skills, so give yourself a little credit here.
In the worse case scenario where the company and you have mismatched expectations with regard to your capabilities. Then there're two ways to approach this.
Option 1: Forget Everything And Run
Admit that you're lacking the relevant skills and give up.
Option 2: Face Everything And Rise
Admit that you're lacking the relevant skills and show the company that hired you, that you're working on it, and you're on your way to becoming "Employee of the Month" for 3,576 consecutive months.
Speaking from personal experience, I always pick Option 2 because it's way more rewarding.
So What's The Next Step Moving Forward?
1) Go online and start reading everything you can about the platform or skills you need to familiarise yourself with.
Join forums and online groups, and seek out subject matter experts to gain insights into what you're going to get yourself into.
In this day and age, you can pretty much learn anything from YouTube, Reddit, Twitter etc. if you're resourceful enough.
2) If there's a dearth of knowledge online, start looking and going for classes or workshops to pick up the skills you need for your job.
Better still, talk to your managers or hiring manager to see if there're company-identified courses for the job that you've been offered. If you're really lucky, they'll even pay for you to upgrade yourself.
3) Reach out to peers in the same industry or company and find out what are their go-to sources of info. Or simply to tap on their experience. Learn from their mistakes and level up faster.
Attitude Always Counts
Skills can always be picked up and platforms can be learnt. But a person with the right attitude and thirst for self-improvement is someone whom companies would kill to hire.
Since you like the job enough to even interview for it, and the company's willing to take a chance on you, why not do the best you can and see how far you can grow as a person and as an employee?
At the risk of sounding cliche, here's a quote from YouTuber Casey Neistat that really speaks to me when I face situations like yours, "The most dangerous thing you can do in life, is play it safe."
If the company is willing to take a chance on you, don't you think you owe it to yourself to take a calculated leap of faith and show them what you can do?