How old and which model?
Easy toi find, It's a rectangular slot on laptop about 1/2' long, by about 3/16th -> 1/4 inch wide.
Normally on the side. Some very old laptops have them on the back.
I have a Very old Compaq (pre HP) that has Usb 1.1. so0 I would image unless laptop over 10 years old its there. The question is if it's usb 1.1 or 2.0 and if 2.0 does it allow charging, some "old" usb 2 did not.
Plug it in and try it.