It will probably cost less to buy a new one.
what model
no, I need help putting it together.
Gun shop or gunsmith
Look up on the Web under "Air Gun Repair" and find a shop closest to you.
Which model? All the different models are assembled differently.
"The proper way to clean a gun is to make sure it is not loaded, spray it with cleaning supplies to get all the gun powder out and then put it back together."
What an answerable question. You have provided oodles of information
If following the instructions in the owner's manual doesn't assist you, I suggest you take it to a gun smith/gun shop.
See the link below for the drawing.
Need make , model of "gun" hi-point c blue 9mm se
look for pictures of the insides on google or nerfhaven.com and match your gun with the picture.
it depends on the model.