A site asked me to switch or add a network

Switching works: the wallet shows which network is being asked for, and accepting changes your active network. Many sites only work on one chain, so this is a normal request.

Adding a network does not work in the released build — the wallet shows you what the site asked for, but the network cannot be saved, so a site that needs a chain outside Ethereum, BNB Smart Chain and Polygon will not work here yet.

If a request names a network you have never heard of, refuse it and look the site up first. Switching to an attacker's chain is one way to make a transaction look harmless.