What is the problem?
Can't install plugins from the menus.
What did you already try to solve it?
Reviewed the logs, however, confused by what it wants.
serial.log or output on terminal tab at a minimum, browser error console if UI issue ... no logs, no support!)
Additional information about your setup (OctoPrint version, OctoPi version, printer, firmware, browser, operating system, ... as much data as possible)