If you insist on playing healer, go back to classic. I am very serious about this to tell you. You can’t even grind as a healer in live server. Of course if you are top-geared, you can, lol. Or please look up for high populated prive servers for l2, there usually u gain much more xp so it must be okay for even non-geared healer to grind. Although you will be fed up with what is waiting anyway after some times.
Althernatively, you can buy adena to buy xp shinning growth xp scrolls to get xp. Really, don’t waste your time on this game fruitless hard grinding.