Hope this will help.
Nope. I'm starting to think I know even less than I thought I knew.
Does that mean you can trade with no money at all?
Thats why its name Futures Trading . you trading for the " Future " and its using leverage or simply like buying power
lets say you capital was $400 and you using 100x leverage thats mean you had buying power or up to $40k that $400 you had as collateral .
but with that high leverage you can easily lose all your collateral. your liquidation price will very close to your entry order.