So on easy levels without power gaming yes you can succeed with 3 classes . These builds probably won’t work for you but I love them
In act 2 with ranger warlock Druid
I went 14 in the main stats early on, dex gloves and other items and you can respec abilities to get the 18’s later
Gloom stalker ranger knight for heavy armor I took halberd, halberd master and blade warlock gives me extra attack plus dip in spore Druid for an extra attack and extra hp. Getting a ton of roleplaying etc
In act 1 ranger rogue and 1 level in war cleric. War cleric extra attack early on and going sword and board with this. Again am I a superhero no but I’m doing consistent damage and a tank