How to test if my investing knowledge is good enough?

I think there's never such a thing as 'good' enough because there's simply so much to learn about investing and trading. Learning is a lifelong process and you should never ever feel like you are 'good' enough!

For myself, I'm relatively new to investing and i find myself learning something new every day.

You could try things out on a stock investing simulator- but really trade with the mentality as though you are using your own personal savings. I think many people use simulators but ultimately dont find it useful because they don't feel the pinch.

Ultimately, there is no one person in the world with perfect investing knowledge. Even Warren Buffet makes mistakes and has learnt plenty throughout his investment journey.