Replacing Interior Garage Entry Door - Cinder-Block Wall

[Gmullz]

I'm looking to replace the door that leads into my garage from the inside. It's old and outdated - probably original construction (40 years or so). It's also not sealed as well as a new door would be, and probably isn't up to fire code either.

The trick is, my doorway is cut into a cinder-block wall that separates the garage from the rest of the house. So I feel like that adds some complexities, some of which I am aware of (like the depth of the door jamb), and probably some I'm not aware of.

Here's a video of the door: https://www.youtube.com/watch?v=qUejmo9AspM

I'm hoping to replace it with a door like this: https://www.homedepot.ca/en/home/p.32-inch-x-4-916-inch-primary-6-panel-right-hand-door.1000108114.html

Will I have to custom order a door that will have the proper depth of door jamb to match the cinder-block wall? Is there anything else I should know about mounting a door frame to cinder-block?

[Fishindude]

Strip off trim on one side so you can see what size the rough opening in the masonry wall is.
Order a door sized so that the jambs will fit inside of that rough opening with a little room all sides to shim, plumb and level things.
I'd probably just purchase a standard jamb width made for a normal 2x4 wall.  Order one without brick mold or casing.
Set the door with inside face of jambs flush with interior drywall if possible, so interior is easy to trim out.
Shim between block and new wood jambs to get everything straight, true & plumb.
Make sure shims are placed near hinge and lockset locations to hold things solid.
Pre-drill and countersink the jambs to allow anchoring to the concrete block using pan head "Tapcon" masonry anchors.
Make sure door opens and closes nicely before installing any trim, if not adjust the shims and Tapcon anchors accordingly till it does.
Using a table saw make some extension jambs of proper width on the garage side to cover the remaining portion of block exposed to view.
Shim and anchor the extension jambs same way you anchored door jambs, glue them to the door jambs if you want and / or caulk this joint where they butt together.
Stuff the gaps between jambs and concrete block with fiberglass insulation, or squirt full of non-expanding great stuff foam.
Set threshold to properly seal, shim, anchor and caulk in place as required.  If you need to raise it slightly to get a good seal, I like to use pieces of asphalt shingles for shims as they don't rot.
Anchor the threshold with pan head Tapcon anchors and caulk neatly all the way around.
Trim inside and outside of door with normal ranch or colonial casing nailed to jambs with finish nails.
Paint & caulk.

[Gmullz]

Thanks a lot! Huge help. I'll be following your recommendations pretty closely I think.