Resource Packs

I've seen this question a lot and I need to ask this too, because I didn't find any helpful, I started a new character with my friend, he uses a Mac, when it prompt him to download the resource packs, he accidentally clicked no, now he doesn't have the texture pack, so all his weapons are like a block or an ore, how can he fix this? Please list all possible solutions, thx!
P.S. When he presses esc and go to resource packs, he only has the default minecraft one, and nothing is in his server resource packs folder.

 

The answers to most of your questions are in this thread.