You need to buy 3 Axies and 1 Axie costs at least $200. Or you can just join the Axie discord or reddit and ask for scholarship.

Scholarship is when someone is lending you their Axies, you farm in-game and you get to keep like 60-70% of what you earned. It's a great way to get to know the game and save some money so you can later buy your own Axies