What is it like for closeted pre everything trans people going over the US border?

Sorry if this is a stupid question - I just want to hear about the experiences of other pre everything people on this matter.

I’m a pre everything trans girl who isn’t out anywhere except on Reddit. I have to go to the US for college… can border guards find anything on my devices if I delete parts of my history? Would I get transvestigated anyway? I am not even sure if I can find a trans support group.