Will need to repaint the panel.

Will need to do a lot of prep work and buy proper paint.

No easy way to make it look good if you don't have access to a proper automotive paint setup.

Best DIY is have some single use 2 part paint cans matched and then use a two part clearcoat... will still be noticeable, but if you take time, research and prep it, it might be good from 10'. Not enough room here to explain all the steps.

Scratches through the color coat can only be fixed by repainting the panel. Unless you have the equipment and knowledge of painting a DIY fix isn't going to happen.

No problem, just get some 80 - 120 grit wet/dry sandpaper on a belt sander and sand it out, use high speed and and keep it wet with water and it should look like brand new in no time at all! Good luck!