Models with more than one expression

[ElmerFuddFan]

Ah. They were already combined for me. I assumed you got them from this pack: https://www.deviantart.com/kittyinhiding...-895526067
Anyway yeah that was in blender. Basically what I did was:
1) Go to Object Mode
2) Select the meshes I didn't want (Control+Click to select multiple)
3) Delete by pressing X
4) Select the meshes to join into one (Control+Click to select multiple)
5) Go to Object -> Join
6) Go to Edit Mode
7) Go to Mesh -> Merge -> By Distance
8) Reduce the distance by adding a bunch of 0s (You can skip this most of the time)
9) Back to Object mode
And that results in all the geometry being combined. This only gives you one expression for the model though, and I think what you meant was to have all the expressions combined into one model so you can switch between them; which I don't think is possible unless you switch between expressions by hiding all the expressions except for the one you want to display. With animation that sort of thing tends to vary by program.

Do I open the original and unedited model in there? Also what are the names of the meshes I delete and the ones I join into one?