You’ll have to setup the vpn on your pc and connect the smart tv to the pc hotspot. Can’t install it on the tv or install vpn on your router if it supports it.

Not possible you'll need a VPN router for somebody to tether a VPN connection.

This is the problem with providers who need VPN. Imagine this was someone who was non technical and was told they had to Tether a VPN connection.

https://www.google.com/search?q=express+vpn+setup+on+lg+smart+tv&rlz=1C1CHBF_enIE852IE852&oq=expressvpn+smart+lg+setup&aqs=chrome.1.69i57j0.14751j0j8&sourceid=chrome&ie=UTF-8#kpvalbx=_x6FSXeCoC4GSsAel0LjwCg13