Your CPU can do a lot more than what Windows allows it to by default.

Fixing the problem of the CPU being Stuck at low clock speed in Windows requires changes to the Power Management and Processor State settings, along with identifying software conflicts as detailed ...

Windows 11 Low Latency Profile triggers real-time CPU spikes for smoother Start menu and Search experiences after KB5089573.

Your PC has been logging why it's slow the whole time and one command gives you the report. Why aren't you running it?