Why isn’t it giving me the option to request taxi and stuff?
Because you’re on Unicom.
Unicom is what you have when there’s no ATC available to announce your intentions.
It’s only Unicom on the Casual Server for example.
Frequencies can be manned on Training Server and Expert Server and there you will be able to request stuff if someone is occupying that frequency.
Only when there is live atc you can have interaction with air traffic control.
Yes, you need someone to be doing ATC for the airport your at for interactions. To find airports with ATC they will look like this on the main screen: