Only submit your PSAT scores if you are applying to SLE. Otherwise, you lose nothing by waiting to open your file. Take an SAT or ACT prep course. talk to your college counselor. Take the SAT or ACT in the late Spring after the prep course and when you have given yourself more time. Have your scores sent to USMA. Open your folder in the summer.
From personal experience iwth one of my kids, a low PSAT or early test score will prevent USMA from automatically opening your full application next August. (then you have to share updated scores--and your full application will open--but save yourself the trouble, unless you are applying to SLE, which you should.)
Only share these early scores if you are applying for SLE.