Because of that, I was level 1, and I only had one quest I could do, which was to find Griff's fruit and turn Stingtail over to Griff, because I couldn't win any of those fights at level 1.
You need to explore more. There are plenty of places you get XP from without fighting anyone. If you sneak around aimlessly you can get to level 3 without fighting anyone at all if you wish. Eventually.
If you leave the prison for the marshes you can get to level 4 without fighting anyone but you're pretty much obligated to after that if you want to progress.
(In any case, I also didn't have enough Strength (12+) to pull the spear from Withermoor, which meant he didn't reveal a secret way into the prison.)
You don't need to pull it out. You can break it if you don't stumble across items that give you a strength boost. In any case there are numerous other ways into the prison such as up the ladder behind the necro saleswoman or through the cave with the fireslugs all of which give you varying amounts of XP, are not mutually exclusive and don't require you to fight anyone
(However, I do not think that respawning enemies is the only way to solve that, instead I'd prefer if new areas, more low-level enemies, and more low-level quests are added instead.
I agree with you there. IIRC there is only one level 1 fight - the freshly buried corpse. Perhaps the voidwoken are level 1 also I can't remember. Not many in any case. The game tries to coax you into fighting the crocs straight off which can be pretty suicidal.