MenachemBesides, honestly, I can't help but wonder if the toxicity in pugs isn't a good thing; it pushes people towards actual teams where they can reliably play with people they like.
getting vocally angry at a new player wastes time in comms and will only make him play worse or not want to play at all due to feeling like a burden imo
best thing to do when he makes a mistake is be cool tell him what he did wrong, not scream at him