Should I go an investment course or pay off my loan first?

Paying off your loan first is ideal to avoid debts. Always have a safety net in place before investing.

Pay off the loan first! Even if you go for the investment course, provided it's effective enough, you probably still need some capital to before you can start investing. That being said, the investments you need must generate you 4.75%, and it will take some time to materialise too.
Therefore, by paying off the loan, you're shelving off the loan that will continue to compound, assuming you let it snowball.

Definitely your loan first. Bear in mind that even if you go for the course first, you still need to handle the problem of paying off your debt with the additional interest. If you were to pay off your debt first. You can slowly find a way to earn back and go for the course

Pay off your loan first. There's no guarantee that your investment course will let you make money (but you're guaranteed to have to pay the course fee). But by paying off your loan, you immediately save on the interest, and that's guaranteed.

After that, settle your coverage and rainy day fund, and then you can look at exploring investments.