So, i've made a Humanoid NPC (it is welded properly, the humanoid is functional and it works in general), and i'm trying to use MoveTo to make it walk somewhere. However, when it starts walking, it treats the side of it's model like the front and it turns to the side while walking. Would there be any way to change it so that it faces how it's supposed to?
Likely, the Torso part got rotated when you were making your NPC.
Change the Front surface of the Torso to 'Hinge' or 'Motor', and rotate and resize it so that it's pointing forwards. You may have to redo your welds after this, though.
What you should do is insert a decal into the torso and set the face to the front. If the front is the side, that is your problem. The parts are set up the wrong way. Re-arrange and re-size the parts and weld it so the decal is at the front, then delete the decal.