We live in exciting times, where so many new Enterprises have been introduced to canon in the span of just a few years.
Recounting the intros from top of my head:
USS Enterprise NCC-1701, TOS - 1965
* Constitution class, Pilot Version
* Constitution class, 2265 refit
(ISS Enterprise NCC-1701, TOS)
NCC-1701, TMP - 1979
* Constitution class, Enterprise class refit
NCC-1701-A, TVH - 1985
NCC-1701-D, TNG - 1986
* Galaxy class
* Galaxy X class refit, AGT - 1990s
NCC-1701-B - 1980s
* Excelsior class, TNG (wall panel)
* Excelsior class refit, GEN - 1994
NCC-1701-C - 1980s
* Ambassador class, Narendra class/prototype version, TNG (wall panel)
* Ambassador class, 2330s refit, TNG (Yesterday’s Enterprise)
NCC-1701-E - 1996
* Sovereign class, FC
* refits, NEM - 2002
Enterprise NX-01 - 2001
* NX class, ENT
* NX, Columbia class refit, PIC - 2022
(ISS Enterprise NX-01, ENT)
NCC-1701 (Kelvin timeline) - 2009
* Constitution class, ST1
* refit, ST3 - 2016
NCC-1701-A (Kelvin timeline) - 2016
* Constitution class refit, ST3
NCC-1701
* Constitution class, 2255 refit, DSC - 2017
* 2259 refit, SNW - 2022
NCC-1701-F - 2023
* Odyssey class, PIC