I believe what you can do is possible, but a bit tricky. I believe it would imply setting up an internet bridge between your network and the network your Galileo is at. If you wish to continue I'd suggest you to take a look at How to make a (real) network bridge with a Mac
However in my opinion a simpler solution would be to simply remotely connect your Mac to a computer in the lab that is connected to the Galileo. That way you would be able to connect your board through PuTTY, Screen, etc. I believe this is the fastest and simplest way to work remotely from home with your Galileo.
Thank you for your help.
the Galileo is at the lab in my university, when I'm there it's not a problem to use it because I can use a desktop very well prepared to do these kinds of things. The Galileo is connected in internet and has a IP and I can't take it to home, that's why I need to learn how to do that using my mac, so I can work in my project while I'm at home too.
I'll check the link you left here.
As I said before, I believe what you want to do is possible. Nevertheless it is a bit tricky since you'd have to set things up on both ends. If you plan to continue this way, I'd suggest you to take a look at Re: Internet Bridge it is about creating an Internet bridge on Edison,however it may help you with your Galileo.
Also, as I said in my previous post I believe the simplest and easiest way to use your Galileo remotely would be to connect the Galileo to a computer and then access this compute remotely using a software for remote access.