If all you need a web browser using Tor, use Tor Browser which uses Firefox ESR as its base, is very easy to use, and it includes everything you need.

Tor does not prevent online services from determining that you're using Tor so keep this in mind! This should be used for privacy, and not anonymity. Ubuntu versions older than 16.04 / Linux Mint older than 18.x don't use systemd, so some things in this article won't work for such old versions.

This should work in Ubuntu 16.04 / Linux Mint 18.x, Ubuntu 18.04 / Linux Mint 19.x, 19.10 and 20.04 / Linux Mint 20, Ubuntu 20.10 and newer, as well as Linux distributions based on Ubuntu, like Pop!_OS, elementary OS, and Ubuntu or Linux Mint flavors, like Linux Mint MATE or Kubuntu, Xubuntu, Ubuntu MATE, and so on. The instructions below include steps for setting up Privoxy, in case you want to use Tor with an application that doesn't support SOCKS5 proxies, manually setting up the proxy in case torsocks fails to launch an application, as well as configuring Tor to use country-specific exit nodes (so you can specify from which country your new IP should be), useful if you want to bypass country restrictions / censorship and you don't afford a VPN (but if you can, go for the VPN option!). This article explains how to install the latest Tor Client in Ubuntu 20.10, 20.04, 19.10, 18.04 or 16.04 / Linux Mint 20, 19.x and 18.x, and using it as a proxy with various applications. Tor (The Onion Router) directs Internet traffic through a volunteer overlay network, with the purpose of protecting the user's privacy and freedom.

Tor proxy service