How to find right mentor(s) for your first startup?

I am a second year student pursuing CS from India, mostly doing open source and freelance. Recently me and my friend planned to take a shot at a startup. And while developing a product we realised that we often say "this MIGHT BE the problem", or "this MIGHT BE the best way to solve the problem". But after researching and discussing for days, we realised how far off we were. We realised that with every new idea we sort of vouch for it and in hindsight don't see any problems that should be obvious. Since we are just tech people, we really think that it would be good to have some sort of mentor(s), to at least quickly validate/invalidate whatever we come up with and point us to the right direction.

My question is, how do I, a guy from second year of college, who has never attended a single offline class (due to COVID) can approach mentors? I do realise that many people here met many such people in real life who changed their paths or even passively guided them, what would you suggest to a homestuck kid from India???

Please feel free to provide other generic advice too, so that others can benefit from this thread. Thanks :)