After minecraft updated, whenever I want to join a MC multiplayer server, it says "Can't connect to server"

After Minecraft updated, I have looked for solutions for this problem like resetting my internet, reinstalling minecraft, etc. Nothing worked and I want to know what the problem is so I can be able to play multiplayer. Also I tried doing older versions and the same issue happened, what is the problem here and how can I fix is so I can play my favorite servers? (For some reason Mineplex only works for me, also I am on a laptop).