How to restore deleted pictures from LG K8? I accidentally deleted some pics of my daughters that was sent in a txt. I found some recovery apps to get them back but my phone has to be rooted.

How do I root my phone and what does it mean?
You will not need root access if the device runs android 5.0 or above, A photo recovery software is able to recover photos easily without root due to the new changes in Android 5.0 and above, It's still not clear why Android has left this out of the root only features but it's still handy. 

The first thing to remember with data recovery is that deleted files are not actually deleted but rather marked as replaceable files ready for new data to replace it, this means you should not to add any new data to the device or it will overwrite the deleted files, so if you fill up the device with more photos, all the old ones will be non repairable ( unless you have software that is powerful enough ) .. Some people say it's possible to repair a file that has been overwritten 7 to 36 times but i don't believe that.. 

Anyway, the first thing you should try is DiskDigger
This link is to their no root version Photo Recovery    

A tip for using disk digger :   Sometimes changing the default storage path in settings > storage will allow DiskDigger to scan the SD Card as the internal storage. It's sometimes helpful to reverse the default storage device between scans if you couldn't find the files you're looking for