Geoblocking certain pages

Site URL: https://www.thenote.no

I run a bar in Norway and it is illegal for us to advertise prices on our website.
 

Due to covid restrictions I’m trying to implement a way we can take orders from the tables. I’ve managed to implement a web storestore, that connects to my POS and embedded it onto my site within a code block.

I can lock the page with a password and put them with a QR code on the tables, but I was wondering if it’s possible to either geoblock the page unless they’re at our location (e.g set a lat and lon for the location) or if it is possible to whitelist our wifi and blacklist everything else so they can only access the page when connect to our wifi? Failing either of those options, is there a service or plug-in that I could add into the code block that restricts anything at all? 
 

Thanks.