Hey man, I know this was a while ago, but it's a pretty common thing. I personally buy these: https://www.amazon.com/Ernie-Ball-Regular-Slinky-Nickel/dp/B0002M6CVC

Later on when your fingers grow stronger you can play around with some other gauges! I think Rocksmith has a okay tutorial on replacing strings. but here is the one I used when I broke my first string (doing the same thing): https://www.youtube.com/watch?v=4CtqfHmssx8

I'd recommend buying a string winder from your local guitar store too. And like u/splslick said, I would use those websites. I personally still use https://syngates.com when I practice!

Enjoy!