TeamViewer

TeamViewer QuickSupport will download to your device after you click the download link at the bottom of the page.

If you're starting QuickSupport on your Mac for the first time, you will be prompted with the following dialogs...

To allow the access, click the buttons shown in the dialog. Eg. Under Screen Recording, click on Request Access... then confirm by clicking on Open System Preferences.

Which will bring you to the Accessibility section of the Privacy panel

For the Accessibility access, you will need to click the padlock icon in the lower-left corner to make changes. You might be prompted to enter the credentials of an administrator account to continue.

Repeat the check next to TeamViewer in Screen Recording as well.

Finally you're presented with your credentials to provide to your support member.