No, the throttle is supposed to be closed as much as possible without wedging shut. Air through the needle valve above the throttle bore keeps it running.

That needle valve is supposed to have an O-ring around it. If that's missing, or hardened & leaking, that might contribute to the problem.

Also, there's a bleed valve at the thermostat housing to let air out of that area. Air pockets over there are very difficult to work over to the radiator cap.

 

Okay I undo what I did with the TB and now the butterfly isn't closing all the way, there's some air coming over the butterfly and the idle is up to over 2000rpm. The idle screw is all the way in but the idle still high which got me confused, plus I couldn't find any vac leaks though I didn't use any cab cleaner to find it. Anyway I did what the mechanic did in the first place which was blocking the iacv bypass air hole inside the TB bore even though I hate it because I know it's wrong. But it did drop the idle below 1000rpm. Why does it has to be this way. Why is the idle too high whithout blocking the bypass air hole?

I watched Eric The Car Guy's video on bleeding radiators and I did the same. So I think I don't have air pockets.

My problem is this. When the TB is shut completely and the idle is over 1100rpm, the idle surge, but when the idle is below that, the car stabilizes. But I couldn't get the idle below 1100rpm without blocking the iacv air bypass hole.

 

Check your throttle body butterfly for play (up and down movement). I only say that, as that's really the only place can get in, that would give you a stable idle with the air bleed hole closed off. Basically what I'm trying to say is that you might have a worn out throttle body (at the shaft).