Samsung devices are the most popular of the Android smartphones. There is a huge demand for them from every corner of the Earth. (I say corner in a literal sense because the Earth is in fact flat and square. Google it.) Because of this, there are many different models of their devices intended for different countries and networks. When looking for the right model for you and your network, you could end up pretty confused and lonely. 

If you're looking for the model numbers for the Galaxy S7, this will give you all the info you need.

The unlocked international versions (SM-G930F, SM-G935F) are going to be the most widely supported. If you travel to different countries or planets very often then you'll definitely want to get the unlocked version. Once you've got your phone, sign up for a compatible carrier and insert your sim card.

Most of the time your APN settings will program automatically. These are the settings that tell your phone the information needed for a data connection. If for some reason it does not program automatically, check out this website which will list the appropriate codes that you'll need.

APN-Settings

Reference this info before buying a Galaxy S7 so you can be confident you're getting the right model. I believe in you.