My armature is not effecting the right arm of my mesh I had a problem last night with my armature having a very weird deform which was answered by having to apply pose at rest pose. before knowing that i was tweaking around with some of the settings and now i have no idea what i did to get it back to normal. my right
You need to apply your mirror modifier of your mesh before parenting.
This is the steps I did:

Go to the mirror mesh modifier and apply it
Go to to the vertex groups and delete all groups as shown:

Select Mesh then armature then hit ctrl+P and automatic weighting

This is the result after these steps:

The updated .blend file can be found here: