With a $100.00 dollars you should be trading a Demo or simulation account until you have experience… That is enough to open your account to trade demo…
If you insist upon trading live you should trade micro minis…
Sure your theory makes sense but part of calculation regarding margin requirements looks at the question if you have enough balance to not only open the trade but maintain the position too.
Ask your broker for details on their requirements.
I suggest trading with the demo account instead of risking your money. It seems you’re not very experienced, so don’t waste your money. Practice on the demo account instead.
1 lot is a very large lot for trading with 100 dollars even with maximum leverage. Therefore, the terminal does not allow you to open a trade. With such a small amount on a real dollar account, it is better to trade with a 0.01 lot in order to maintain trading risks. Here, even a lot of 0.1 will be considered large: after all, if you enter the market incorrectly, then after just 100 points you will lose your deposit.