I just bought the Avast VPN and my computer is all messed up. Everytime I start up the date and time are off by a decade. In addition, I only get a white page instead of Avast. I uninstalled Avast pro installed avast free and it still is a white page.

Why is this happening? vpkw

avast has nothing to do with the date/time.
Looks like you have a dead CMOS battery.
Replace it, set the correct date and time in the BIOS/Uefi and check if they stick.