Cmd-f2 on your iMac (while plugged into your MacBook over usb-c), will allow you to use your iMac as an external display.

Many people are only able to work on machines provisioned by their companies. Even if you could get your home iMac provisioned during Covid, you may be wiping out all your personal data and now you are dedicating a machine you paid for to your company.

It's my personal machine and I can only use work-provisioned computers for (entirely reasonable) security reasons.