In that case is there a guide for how to play this seemingly impossible to beat game? I get destroyed on the second quest, and even if I run to the boss and lose on purpose to advance in the 3rd quest I can't even do that because impossible to beat enemies are in the way.
The previous person provided links to the guides, so I'll skip that. However...
Something I feel like people miss a lot is
use the Battle button. It's how you can gain experience so you're not underpowered.
Certain fights (mostly) require certain weapons. Boss fights usually/always have something in the level that you need to do in order to have a chance in them.
If you choose to play it without a guide, you'll be playing the maps over and over again to learn everything you need to know to play them optimally, but once you do, you'll have plenty of room left to use the battle button. Also, avoid dying, as it costs 10 turns, which is a huge waste of XP. If I died, I'd usually restart.