The initial steps of installation
1. Get the DEB setup package for the ProtonVPN repository
Download the ProtonVPN DEB package
2. Install the ProtonVPN repo
Double-click downloaded DEB package to install the repo using your default package manager.
3. Update the apt-get package list
$ sudo apt-get update
4. Install the ProtonVPN Linux app
$ sudo apt-get install protonvpn
It should be noted that from step 2 onwards, typing the sudo apt update command does not update the program repositories, although this problem persists for other similar programs.
Code error step 3 :
Failed to fetch https://protonvpn.com/download/protonvpn-stable-release_1.0.1-1_all.deb/dists/focal/InRelease Could not connect to protonvpn.com:443 (10.10.34.35), connection timed out
Code error step 4 :
Reading package lists… Done
Building dependency tree
Reading state information… Done
E: Unable to locate package protonvpn