This depends on your max drawdown and cushion needed for margin, nothing more.
So for example, if you have a win rate of 50% you can expect ~ losing streak of 10 over 1000 trades if every trade is independent.
If you lose $500 each time, then you need a drawdown of at least $5000. I'd double this because you can have a losing streak of 10, a winner and then another losing streak.
Then the rest of the account should be funded according to the margin needed to trade the size you desire. I'd double this as well.
Given a win rate of 50% with a 2/1 win/loss ratio where you lose $500 when you're wrong, then I would fund it with a minimum of 20K if you're using a discount futures broker.
If you don't know these numbers then you shouldn't try to fund an account yet.