I’m not really acquainted with the platform, but I’m pretty sure there are already some videos around that can help you with the process, such as these two:
https://www.youtube.com/watch?v=vzNbFUXkToohttps://www.youtube.com/watch?v=4Pw2Ec2u7V8If you’re placing a bitcoin order, the units should be in bitcoins or fractions of a bitcoin, so either the system should not let you actually go through with a 50 BTC order having a 10K $ test configuration, or maybe you’ve got it configured in sats.
In any case, following the procedure in videos such as those included above should guide you through the process well enough to begin with.