Sword Art Online Season 2/3?

Have just watched season SAO on Netflix. It exits a series of the same name with a squadron, which looks more like a reboot than a second season. Is that true, or where / what is the 2/3 season?

Sword Art Online (S1)
Sword Art Online II (S2)
Movie Ordinary Scale
Sword Art Online - Alicization (S3)
Sword Art Online - Alicization's War of Underworld (S3 Part 2 from October 2019)

Netflix has the first two seasons, everything else is on Wakanim. Gun Gale, however, is a spin off and not the sequel.

There are currently 3 seasons.

Sword Art Online (Season 1)
Sword Art Online II (Season 2)
Sword Art Online -Alicization- (Season 3, Part 1)

The squadrons are sequels to the previous season.

There's still "Sword Art Online Alternative: Gun Gale Online," which is a spin-off.

SAO - S1
SAO Extra Edition Movie Recap 50% of 1
SAO II - S2
SAO GGO - Spin-Off
SAO Ordinal Scale - Movie between S2 and S3
SAO Alicization - S3
SAO… Underworld - S3 Part 2

GGO is also in Season 2. Lol

What I mean is a spin off.

I would say net spin offs usually have no effect on the series