Haven’t paid taxes on stocks, ever. How do i fix this?

I have $41k in my brokerage account. I started putting money into it roughly 3 years ago.

Didn’t claim on my 2020 or 2021 taxes. Not sure what I would have owed, if anything.

Can I just start at 1/1/2022 and pay what I owe going forward? Would that trigger some kind of audit or something with them questioning where all these stocks I now own came from?