Hello
simple solution:
- press the Windows key + I open the windows security settings. Click on "Update & Security" (if you do not see it, just scroll the mouse down).
- go to Windows security> anti-virus and threat protection> settings for anti-virus and threat protection.
- Click Add under exclusions to exclusions or remove.
- Select Add exclusion> process.
- Enter MsMpEng.exe and click Add.
Complete guide with more methods and procedures
https://geeksadvice.com/how-to-fix-antimalware-service-executable-high-cpu-usage-on-windows/