SharePoint Admin & Useful URLs && SharePoint REST API Endpoint URL List - 450+ Links
I compiled a list of ~250 Site/Site Collection Admin Links, as well as a variety of other useful links for Site Administration shortcuts. I tested these on SP Online only. If you aren't completely familiar with the URL structure, it is https://.sharepoint.com/sites// <-- Then the rest of the url on the linked google sheet.
For the members of the sub who use the REST API, there are ~230 endpoint URLs on the other sheet.
Where possible, I tried to include required parameters/inputs.
Feedback / Additional links welcome via comment. I will add them to this list.