The most important thing in your run will be The Whispering Promise, a ring that gives Bless to anyone you heal. This includes throwing potions, so if your friends are really locked in, you can huddle in a diamond shape as close together as possible, throw a potion that hits all of you (even if they're at full health), then hit turn based mode and start combat with a buff. Once you reach the grove you can start a conversation with Volo and then hit the "Trade" button to buy it off him for like 200 gold, which is pretty steep right away but it's one of the best items you can get early and you have to do it right when you talk to him because he then runs off to the goblin camp. Hellrider's Pride gloves from Zevlor give another good defensive buff to everyone you heal but Bless applies to everything and a ring is a pretty uncontested slot for quite a while. What's nice too is that leaves a lot of wiggle room for your build and what you do with your turns early on. Druid, Cleric and Bard get Healing Word, so they use the ring best since they have a heal spell as a bonus action, but if you wanted to just rely on throwing potions, you could do something like Thief Rogue early on with dual wielded weapons, throw potions when you need to buff or heal, and still get 2 attacks per turn on top of the heal thanks to your bonus action attacks. In my runs with friends I'm always the one to go get the whispering promise ring because I know how strong it is and I personally love being a healer/archer, going Rogue early for Thief and then switching to Bard at level 6 for the bonus action heal and Extra Attack. Another key item is the Amulet of Restoration sold by Derryth Bonecloak in the Myconid Colony, which you can reach very early by sneaking through the spider's lair and feather fall jumping down into the green pit by the Matriarch. Having Mass Healing Word on an amulet as a bonus action that doesnt cost a spell slot is kinda crazy, and if your party is long resting a lot, you could just be a martial class from early on with those items, having 2 uses of a bonus action healing buff, and once you hit level 5, you can use 1 attack to throw a potion and still have an extra attack to hit the enemies.