Should I be saving this money or invest this money for my upcoming plans (marriage and bto costs)? Thanks for reading and I look forward to the replies. Cheers!

Well, it appears that you have both short, medium and long term financial goals to achieve.

Short Term : Marriage cost. It can be as low as less than S$100 bucks to just simply ROM. Jokes aside, you should be looking to cover the cost of a typical wedding: Proposal Rings, Engagement Rings, Photoshoot, Banquet, gifts and dowry etc. This can work out to about ~S$30,000 depending on the location of the banquet and the cost will increase every year. You may check out the Seedly article for more information: https://blog.seedly.sg/cost-of-wedding/

Medium Term: Property and Renovation Cost. You need to make sure you have sufficient cash for renovation, and also sufficient funds in your CPF-OA to make the downpayment of your first home. Do check out the 2 articles from Seedly on this: https://blog.seedly.sg/steps-to-take-to-buy-a-h...
https://blog.seedly.sg/a-guide-to-buying-your-f...

Long Term: Retirement.

In the long run, you should aim to build multiple streams of passive income for your retirement on top of CPF Life, and there are several options to invest it. For that, i would suggest that you start by reading up more about ETFs, Unit Trust, Roboadvisors.

Lastly, do not also underestimate the need for insurance (even though this is a topic not favoured by any). Ensure both you and your future spouse are adequately covered, and there is no better time to buy since you are now young and healthy!

Speak to a financial planner that is able to provide you with a roadmap to achieve those small goals that were mentioned above based on the income of you and your future spouse. If you can't find one that is capable enough, I would love to 'shamelessly' offer my services. Feel free to reach out to me via https://www.facebook.com/brandan.chen

I believe you should focus on "investing " in your marriage at this point. You are going to build a marriage portfolio - house, renovation, insurance, etc. All of these requires expenses and loans.

At this point of time you should also take the time to build up actual investing know-how, understand the types of instruments - their cost, their risk-reward factor.

Although Investing is best to start as early as you can. But focusing on your new life with your partner is also part of it. Remember 2 is better than 1 therefore you and your spouse can consider to build your investment portfolio together.

Win-Win for both marraige and nest egg.