Fallout 1 obviously takes place before 2 this is already simple enough although fallout 76 takes place before both of them. but in the show Shady Sands is destroyed by hank not The Vault Dweller my headcanon for this is that Shady Sands was rebuilt, this can be backed up with the show taking place in 2297 Shady Sands can be rebuilt in that time even in a dying world.

Fallout 3 and 4 both feature The Enclave being destroyed (dialogue from BOS members in 4) but in New Vegas you can side with the Remnants (Enclave members), I don't believe Courier 6 sided with NCR Caesar's Legion or any sub faction I believe the Courier 6 sided with Mr. House as the Platinum Chip was meant for Mr. House I don't believe the Courier would choose a military like faction but would stay loyal to House. Fallout 3 has the BOS destroy The Enclave but we see Remnants near Vegas and win The Battle Of Hoover Dam if you choose them but in the show that takes place 20 years later and the Control Station Enclave gets destroyed in 2 this must mean that The Enclave has outposts all over the wasteland slowly growing (explains the puppy incinerator scene takes place at a outpost)

The Brotherhood Of Steel's Prydwen is shown in the Fallout show this is just a theory though but I highly doubt the Brotherhood Of Steel has enough resources to remake the Prydwen (despite how big they are its a lot to make) so Nate might have went Minutemen or BOS as the faction they chose BOS is more like a military faction out of all the factions in 4 (Nate was in the military annexing Canada yes I know it isn't true but he could have been fighting China during the Battle Of Alaska that's why he doesn't need power armor training) or Nate could have chose BOS and Minutemen that's my guess. Now the show leaves tons of lose ends with Vault Tec (implied) saying they would drop bombs I think the US fired first at china during a battle and then China fired back and the US president left into his own vault to be protected as he knew that it would be suicide and the world ending. Now you may be asking "Well the bomb in megaton had the Vault Tec logo on it what about that?" ( https://fallout.fandom.com/wiki/Atomic_bomb_(Fallout_3) if you haven't seen) I believe Vault Tec had an overseer or have Enclave members come and place a bomb in The Capital Wasteland to see what would happen (I highly doubt they used a overseer.) Enclave outposts can turn into Enclave military posts that can be why we see the Enclave play a semi huge role in the show. Enclave and Vault Tec work together as a organization that's why they have Cold Fusion.

Thanks for reading my guide sorry it became theories sometimes. It isn't the best theories or headcanons I made this while its 3 am where I live so there are flaws and stuff cause I'm tired n' stuff but thank you for reading this far.