I know Genesect and Golett/Golurk can learn Fly. But what are some others?
Depends on what you think can fly or not. Here is a list of them. I think Doduo because it has no wings and Mew, but it can learn everything so... yeah.
Arceus can, and so can Rayquaza (I know it's Flying type, but I don't think it looks like it).
This is slightly opinionated but here's my take on it, as of Gen 7
Giratina* [Origin Form is wingless] (GHO/DRA)
Tapu Koko (ELE/FAI)
Hoothoot - wingspan is so small that it doesn't look feasible
Kyurem - same problem
Vullaby - same problem
Rayquaza - wingless, but a legendary with a connection to outer space, and one might venture that it could fly going solely by appearance in this case
Arceus - no wings, but it's pretty much God, so not on my list
Celesteela - extremely heavy pile of metal, but the base of its body and arms resemble rocket launchers