The antimalware executable was using large amounts of my disk on task manager slowing down my pc so I searched online as to how to fix the issue, I came across this discussion.

https://answers.microsoft.com/en-us/protect/forum/protect_other-protect_start-windows_10/antimalware-service-executable-very-high-disk/84168369-39ca-44df-9c5a-4c054735abcd

It requires you to change the properties of the windows defender scan scheduler in the task scheduler however it was missing from the task scheduler.

all the other tasks are there like the Windows defender Cache Maintenance, Clean-up and Verification.