The relationship between leverage and margin is just a gearing ratio between the money required to open a deal and the deal size.
Higher leverage means lower margin requirement. lower leverage means higher margin requirement relative to the same deal size.
There is nothing more to add.
Better to decide how much you are prepared to risk on a deal.
Then decide how far your stop loss will be placed away from your entry price.
Then trade an appropriate lot size so the value per pip does not exceed it should your stop loss get hit.