How do I reset my iPad Pro? I have my iPhone but I don’t understand what to do specifically.

You do not need a computer or iPhone to reset your iPad Pro.

See this Apple article for more information on how to reset your iPad Pro...

https://support.apple.com/en-us/HT201252

Assuming you can access the iPad, you can reset it from the iPad's own Settings App, in Settings->General->Reset->Erase all Content and Settings.

If you can't access the iPad to do that, then you require a computer to restore the iPad to factory settings.