Handyman - Install 2nd Floor Sliding Door Barrier (Mount Royal)

Hello, A presale home inspection identified I need to have a barrier installed on the second floor at the sliding glass door.
There is no deck so the sliding glass door leads to a drop.
The project involves purchasing the barrier and installing it, hopefully this weekend or by Monday.
I also need the smoke detectors checked to see if they are hard wired and meet code.
Thanks, Josh