Does it need to have at least 10000 USDC to get 50$ per month?

Well, I better invest it to other things, managed and earn..I can go for more than 50$ a month if 10K$ would be invested to something solid like selling goods, products or services for I am also a skilled worker. Anyway, 50$ for doing nothing and let your money sleep for a while because you are only saving it then that would not be consider as profit but only a bonus. Saving is the main key with slight bonus or reward being given to you.