I downloaded CUDA driver - because it said to- but After effects keeps crashing every time I try to upload a file to work on/
You only install the CUDA driver if you have a CUDA compatible Nvidia graphics card. I would guess that you do not. Uninstall the driver and After Effects should work.
Without proper system info and the crash logs nobody can tell you anything specific. You are wasting everyones time by letting us guess around.
I got my answers- thanks for your help- I did need the CUDA download and program update.