When you save a chip, it automatically gets added to your starred section. Me, personally, I like to create a new collection called Logic gates, where I put all of my Logic gates in.
A NOT gate is basically just a NAND with a common input, an AND gate is a NAND gate plus NOT gate, an OR is when you invert both inputs of a NAND gate, and an XOR gate can be created with just 4 NAND gates connected in a specific way.