Do grow tents prevent smell from entering the rest of the house?
They can reduce the smell but won’t eliminate it. In order to do that you need to scrub the air that leaves the tent using an inline carbon filter that is attached to the inline fan that is drawing in fresh air and expelling old air. I would recommend looking into an 8” inline fan and matching carbon filter if smell is a concern with the size of the room you are using. Can go smaller of putting in a 4x4 tent to maybe a 6” fan etc.
Also depends on your environmental conditions of the entire building etc. and take into account summer vs winter conditions etc
No, they don’t.