The insurance company has declared my truck a total loss. Can I keep it and get it repaired?

Yes.  The truck is still your property.  If you want to retain the truck, the insurance company will pay you the value of the truck at the time of the automobile accident minus its "salvage value", the amount it could sell it to a junk yard for parts.  You will have to get it repaired and deal with getting it inspected and having a salvage title issued to you by the state of Georgia.