What are the best root files for a Samsung Galaxy Grand Prime?

[Mallory Cassels]

I actually have a few questions, but they all tie into root information for my device.

I given a Samsung Galaxy Grand Prime model # SM-920L that is a Straight Talk sold phone, not a BYOP. I discovered that it has been rooted and not much else. After researching for a month I have found very little information about the phone itself other than many have had similar questions with no answers.

The root prevents me from playing Poke'mon Go, what can I do to enable playing the game?

The device also has no place to edit APN settings, I would like to change that.

I am unable to use the data while talking on the phone unless the wifi is enabled. Is there a way to change this as well?

My 4g LTE suddenly stopped working the other day, I dialed *22890 and it restored my data, but only 3g.

Things I've tried after every "new" change.
-rebooting phone
-taking out battery for a few
-turning on/off airplane mode and mobile data

I also tried to unroot the device but nothing I tried was successful.

Any information about any of this would be greatly appreciated and thanks to any who answer in advance!!