I'm new to WoW and I wonder how should I start

So, as the title says I want to start a run on WoW.

I have always had mild interest on the game, but didn't have money to pay for its subscription when I had the time to play it.

Now I still don't have a lot of time, but my interest has grown. I would like to play with my girlfriend and enjoy the journey of exploring new places. What do you recommend to fulfill these expectations? I have some interest to check classic without expansion WoW, but I have heard that is easy to get lost.