Couple of general tips:

There are some good abilities for Squires that should pretty much be learned by everyone (off the top of my head: Gained JP Up and Move +1, and I also found Accumulate very useful as something to do to gain JP when no baddies are nearby).

It's probably a good idea to try out some extra random battles early on to get used to the combat system and the jobs. The random battle enemies level up with you, but the story battle enemies don't, so it can also help make some of them easier as well.

During combat, it is ok if a party member dies, because they'll just come back at the end, UNLESS they're dead long enough to turn into a crystal, in which case they're gone for good (unless it's Ramza, in which case game over).

FFT is a great game, so you should enjoy it. Have fun.