In FFII, your actions will determine how and which stats are increased. For example:

• You attack -> your Strength and affinity with the type of weapon increases

• You use White Magic -> your Spirit and that spell's level increases

• You use Black Magic -> your Intelligence and that spell's level increases

Stuff like that. For the HP and MP you basically just need to lose part of it in order for them to raise. This does include hurting yourself, just so you know.

The spells will level up even if they don't do anything (i.e. using Life when everyone is alive).

But apparently the Pixel Remaster has made it so you don't need to mercilessly hit yourself so much to raise HP.

Straight out of the manual, this is the specifics of the stats growth of FFII.

I'm currently playing it and from what I understand, stronger enemies level up your weapon/magic levels faster.

Example: using Cure multiple times will level it up. Same for different spells. Attacking levels up weapon level.

Using spells increases your magical stats, attacking/defending increases physical stats and HP can be gained at regular intervals if you have the boost turned on.

I still don't completely understand it but that's what I've figured so far.

It's like I mentioned. It's what happens in battle that determines what grows.

Spells are raised the more you use them, even if they don't do anything when you cast them (like the Life spell example I gave early). Cure is a fast spell to level because you can use it from the menu, Esuna somewhat too, but certain status can only be cured when the spell is at a certain level. Do understand that using the spell from the menu only raises its level, it doesn't raise your MP or Spirit/Intelligence; those have to be raised in battle.

Hp and MP are raised as you lose them, because you got attacked by enemies or yourself/used magic or got hit by Osmose. Usually, the higher the amount you lose in one battle, the more it raises.

You gain more affinity with weapons as you use that specific weapon type. Having a bigger affinity with a weapon type makes that weapon type stronger for the character (hence why Josef is stronger with no weapons equipped at all, because he starts with affinity for fighting bare-handed) and when selecting Optimize it automatically equips those first. Everyone can also have two weapons equipped, one on each hand (of course, you should still prioritize the dominant hand, as the weapon there causes more damage. Doesn't apply for fighting bare-handed [there's no ambidextrous character in this game]).

Other stats are influenced by the remaining actions, as explained in the manual.

There is another thing I don't understand about leveling.

I was farming Captains at Flynn and some weapons went up to 11 while others stopped at 7. Do certain weapons have a cap on what level they can go up to?

No, they don't. They just have a hard time levelling up. Weapon affinity is probably the hardest thing to level up, followed by spells that you can only use in battle.

Is it possible Max stats in beginning?

It's always possible, in any game, as long as you overgrind yourself. I find no pleasure in that, it's tiresome, time comsuming and takes the fun away, but you do you.

I absolutely don't recommend doing that. Even with a 4x boost at the end of the game, I got tired of grinding (mostly because of how the level system works in general). And weaker enemies give less when defeated so eventually you will be hit with diminishing returns.