you can avoid tethering detection, its easy but the phone itself cant do it. You need special router for that like mikrotik and use the bridging feature for layer 2 NAT. With the mikrotik router being infront with public IP you can share webe easily.

However the process isnt so simple as you have to configure many complicated things both on layers 2 and 3. I myself have done it before but not with webe, rather on student focused ISPs like ask4 that use complicated methods to block that you simply cant find it with google (they dont rely on known NAT detection techniques).