Repair holes in copper pipe
As Ryan said you can solder it (either with soft solder or silver solder use flux will make your life easier to) or you can just use a rubber repair on it either buying a propritory type or just making it your self out of a piece of rubber and a couple of hose clamps.

This is a plumb-quik from Fernco


Keep in mind that you don't have to use the whole thing you can cut it open so it is easy to slide over the pipe and put the cut at the top of the copper pipe then put your hose clamps on and tighten it up . I've used this technique to repair a 6" stormwater pipe that was cracked and was a pressurized pipe with no problem.

Another easy way is to use Ferropre or similar a two part epoxy that sets like a rock and sticks to pretty much anything

If you are going to use Ferropre put on disposable gloves, get a bucket of water and mix the two parts together in the water it makes it much easier to handle as it doesn't stick to your gloves as much then once mixed just smear it over the holes in the pipe.