If the projects you invested all failed then that is telling you something isn't it? First of all, you must have not understood the project or you bought too high and got the worst of the dump. In any case, failures are there to help us succeed so you better learn something from these mistakes.

Secondly, with regards to which projects are good for investing in, well that's good question as no body for sure can tell you. Perhaps start by looking at some loe market cap coins and maybe DeFi too.