Generation of a proper mechanism file

[erangit]

I'm learning to use Mutationpp through SU2-NEMO coupling
I need to create a mixture of humid air.
No problem to create the mixture file ([N N2 O O2 H2O H H2 Ho]
But I have no idea how to create the mechanism file (not the format but which reactions,
their constants, and so forth).
In Cantera, I used to use published mechanisms (in chemkin or cti format)
by places like UCSD, UMINN , Aramco to create the mechanism file. Is there a parallel here?
Sorry if the issue is in the wrong place
Eran