Get an air mouse remote. Theyre like 20 bucks on amazon and you just point the remote at the screen to control the mouse cursor. Mine also has media controls on one side and a full keyboard on the other, and only one set of buttons works at a tim3 based on which side is pointing up so you dont have accidental button presses. It makes it way more functional if you want to do even casual web browsing and the media controls are great for htpc apps. You can also use in browser streaming services this way too though. Honestly one of my favourite peripheral devices that ive ever bought, and super cheap and works way better than i wouldve thought for the price.
Im sure you could find a usb c camera that could easily be obscured or pinned to a lapel or otherwise disguised for cheaper than the price of a pair of smart glasses, or even just wear your phone on a lanyard around your neck with the screen facing your chest. People might think its weird but noone is going to second guess it unless your phone is in your hands actively pointing at them.