Good job cadet!
When you see several planes flying together, even "on top of" each other, check the altitude. Usually there is a good altitude separation.
When AF1 travels, usually a 2nd identical plane is travelling together. One is the POTUS, one is a decoy. You never know which one he's acually in. The SAMxx callsigns are typically seen in this role. SAM45 for the 45th president.