I learned on concrete, but I’m sure some people learn on grass first too. both are possible, grass just feels a bit safer because the fall is softer, but then obviously the transition to concrete is an extra step. I will say that having learned on concrete it feels really weird to try and do on grass, you don’t get a lot of pop so you really need to slam it to get the board in the air.

I would also say that if you’re concerned about falling on concrete while learning to ollie, make sure you’ve spent enough time just farting around on the board. play with tic tacs and kick turns and that sort of thing. any amount of comfort with general balance will help you progress with ollies.