How to play multiplayer with friends?

My friend and I have recently been trying to play with each other on Portal 2 and Counter Strike. he purchased Portal 2 through steam and I sent him a counter strike dl link so we can play since playing Portal 2 didn’t work since we kept getting disconnected before the game starts. When we tried playing counter strike it failed as well. We used the hamachi ip address to try to connect, but it never seemed to work. Neither did the computer input Ip work, is there any way for my friend and myself to play?
Answer #1
tried tunngle. its literally hassle free compared to hamachi.