To change the IP address I use OpenVPN for Android | F-Droid - Free and Open Source Android App Repository + https://protonvpn.com/ config files, in the free version they now give: 2 servers in the US, 2 servers in the Netherlands, 1 server in Japan, but for confidentiality much depends on the browser and its settings and probably on the OS and hardware. Here are some links with which I check for information leakage:
https://browserleaks.com/
https://whoer.net/