Can't use browsers

I have a PI 3 A+ and can’t access browsers. The launch page is OK but I can’t load a website. I have tried Chromium, Firefox and Midori. The cursor also moves on its own.

What operating system did you install?

I have aRaspberry Pi OS, 32bit. Had the same problem with the 64 bit OS.

How are you connecting to the Internet? Home network? Does it time out error out?

I use a BT Home Hub and sometimes the building’s Wi-fi network.

What eventually happens? 404 not found error, etc?