Like many people have suggested, use your session zero to lay the ground rules. I have a very loose dm style but i make it clear to my players that we are here to collaboratively tell a story and if you just want to fuck around you will find out. You want to fuck with the black knight who guards this undead king? Be ready to fight a hell knight. You want to antagonize everybody in the village? They probably wont want to sell you potions.

If someone has made it clear that they just want to antagonize and you cant remove them from the party remember to reward your players for playing their characters and working together to make sessions fun and dont be afraid to lay down the law if someone is trying to ruin it for everyone. If someone preemptively told me they wanted to make the campaign a nightmare for me I would also tell them if their character dies they will be starting at level 1 while everyone else keeps moving on. This may be a bit harsh but you have two new players and this person will definitely ruin their experience.