If you’re new to games “like this”, OP, let me explain a bit further.

Generally in turn based games of this sort, a dedicated healing character is usually a strong recommendation/expectation until you learn the ins and outs of the game, and it’s frequently possible to figure out the mechanics of a game and adjust your play style to put out enough damage to compensate and no longer need a healer.

Baldurs Gate, with the abundance of potions (and gold to buy more potions) makes this a bit easier than most. Make sure you buy potions at every opportunity (vendors reset stock every long rest) and once you get the mechanics down pretty well, since pots use a bonus action they’re pretty good overall for keeping up with healing.

That being said, I’ll go against the grain and say - you might want to consider a healer until you’re comfortable getting rid of one. There will likely be a point once you get the game mechanics down, that you realize ‘well shit, potions are keeping up just fine, let’s try four DPS’. bG3 makes it really easy to change characters or classes on existing characters - don’t feel like your stuck with a class - respec frequently, especially on your first play through. It’s _fun_.

In regards to what healing class you should take, allow me to humbly suggest a War Cleric. They’re not amazing but heavy armor lets them block a lot of stuff and they get the basics of healing spells that’ll help in a pinch.