The dome shape has the mechanical strength of an arch. Bricks are good. You build the inside dimension design out of crap wood.
Then you do all the brick stuff on the outside of that. Be mindful of the keystone bricks at the top (says bricklayer dude).
Wait ? I don't know how long for the mortar to cure and dry. Then set fire to the wooden form inside = done.
Memphis Blues BBQ House cookbook, p15. Author George Siu used a heavy cardboard barrel as the oven form. 48" of 4" galvanized duct for a chimney.
Over that chicken wire. Over that a cement of "sand, clay, cement and water." He never says how thick it is. Looks like 3-4" in the picture on p16.
Wrapped it with wet burlap (jute/hessian?) bags and kept it damp for a week. Then the let it dry for ??? Pulled out the cardboard, added lots of wood and lit it.
It cracked (apparently quite normal.)
Can be done. Sorry I'm not closer to lend a laboring hand.
Pizza will be done hotter than Hades. Long, low, slow southern style BBQ ribs & chickens go 3+ hrs at 275F.
I've done that for years with 100% success.