What do you mean before you knew what you were doing & tried removing the caliper to change the pads? If you stripped the bolt heads you most likely were using the wrong size wrench/socket or you didn't have the wrench/socket completely on the bolt head.
You do need to remove the caliper to install new pads! Remove the caliper bolts, then work the caliper from the rotor. After the caliper is off the rotor use the C clamp, one side on the caliper one side on the old pad & tighten the clamp to compress the pistons. Repeat for the other side of the caliper. BTW you don't have to remove the brake line. I'm not sure if you have purchased a repair manual or not, but obviously you are a beginner so you need one when working on a car. Even if it's just a Hayne's manual.
You really need to know your limits, if you can't or don't know how to fix the issue then leave it to someone who does! At least have some around you to help that does know what to do. If you think you are saving money by doing things yourself, you would be wrong. By not knowing what you are doing you are cause more problems costing more & sometimes not doing things correctly can maybe cause injury to yourself or to someone else.
I think it may be time for you to just let someone else to work on the car.
| 
Threaded Mode
Rx7Forums.com