1. Run a thorough scan with your Antivirus program, plus with Malwarebytes.
2. Most probably the typical issue of drivers. Or one program colliding with another. If you have an idea of when this started, you could try the basic method of Recovery: Control Panel\All Control Panel Items\Backup and Restore >>> Recover system settings or your computer >>> Open System Restore >>> there you can find options, note the options to "choose a different restore point" and "show more restore points". Restore points are quite safe, but you may loose some later installations. Hard to tell. And if uncertain, you can always get back.
3. What's using your CPU? You can see that by pressing Ctrl+Alt+Del simultaneously, then choose Task Manager. If...