First, I created a 2D Sidescroller earlier today, and without realizing how stupid of a decision I had just made, deleted everything that originally came with the template. Of course, I didn’t realize it one bit until I finished building the world and wanted to add a character, only to realize the template’s pawn had been deleted forever, and I tried going to the Unreal Engine 2D Sidescroller tutorial, which used the template’s pawn, so no luck there. My first question essentially is if you’ve already deleted the 2D sidescroller template pawn, how do you create another controllable pawn with custom graphics?
You should be able to create a new template project and migrate the assets you created over to that.
As to the second part, I suggest keeping posts here to a single question at a time. It’s easier for us to manage, it allows others to find existing solutions, and it improves the chance of getting your questions answered.
You can also add again the template files if you go to Add New → Add feature or content pack → pick 2D side scroller and it show add it again, unless you’ve deleted the templates from the engine.