Hello there, i dont know how to mine crypto
BTC with ubuntu, any ideas? Thanks

If you like Linux systems then use Hive OS.
You can mine any altcoins or join nicehash service to get rewards in bitcoins or other coins.
Hive OS is the best system for mining on Linux where you can start mining in 5-10 minutes.
In ubuntu, you will face different difficulties to configure the video card settings. If you don't want to take the easy way, then on ubuntu mining is possible.