Computer Freezes and Doesn’t Respond

Recently, my computer has frozen several times and stopped responding. When this happens, pressing any shortcut keys doesn’t work; I have to hold down the power button on the tower for about ten seconds to force a shutdown. Then, when I restart it for the first time, it usually gets stuck on the standby screen and can’t proceed to the PIN screen. It doesn’t return to normal until after I shut it down a second or third time, wait a while, and then restart it.

This usually happens when I have several tabs open in Edge or Firefox and then try to open another program. The computer freezes immediately—the mouse cursor moves, but clicking anywhere has no effect.

I’d like to know what’s causing this and what I should do to prevent it from happening again.
OS: Windows 11
RAM: 32GB