hi redsusan, first of all have you tried in safe mode, does it still happen. Also have you tried connecting to the net via ethernet? Does that work ok. If so, how close to the router are you when trying to connect wirelessly. If not close, can you move the pc near the router just to see if things are any better via wireless. If not consider updating the driver on the wireless card.
OnePlus 5T review: Hands-on