Do you have a phone that can establish a wifi hotspot? You may be able to connect the Kindle to that. I often did that rather than connect my (wifi only) Kindle to each hotel wifi, which was a long-winded process.

If you use an old phone - which I do occasionally just for calls and texts - the 2g network won't be switched off in the UK until about 2033. Unless you use the 3 network which never used 3g in which case get a giffgaff SIM.