Question stated above!

I just don't want to pay for anything... and I don't know if you can get the best items without paying. Like when you pay for items in the cash shop do they make your character stronger than the ones you can get in game? and will I be able to be as good as characters as good as I am who do use the cash shop? thanks

Yes, Maple Sory is still fun even if you don't buy from the Cash Shop. Items from the Cash Shop cover your current items. They change the appearance, but the stats stay the same. And using Cash Shop items doesn't change how "good" of a character you are either. They (in most cases) just makes you look better. There is though, AP and SP reset scrolls which allow you to change your stats and skill points to get a boost of damage or whatever.
As I do not useCash Shop items, I can also tell you that when a bunch of people around you are using Cash Shop items it can get annoying sometimes that you can't get them.

There is some cases where it seems unfair. Like when they release the 2X exp cards. Some kids (and adults) have the money to afford those. While everyone else has to level at a normal rate.

To help me get over the fact that I spend too much money on NX cash I think of it like this:
If i wasn't playing maple, i would be either buying xbox games, renting movies, shopping online, or some other activity which would cost just as much money. I have a friend who plays maple JUST because it's free. He's never spent any cash on his character yet he levels faster than me and he loves his outfit. It's all about perspective.

Sometimes I pull off an outfit of my own with some newbie clothes. Yes MS is fun without using items from the cash shop

I played MS for a year without any cash-shop item. In fact there was no cash shop when I started playing. And now I only have bought shop permit and pet.
But it still is fun to play even without that stuff.

Shop permit and pet are the best items in my opinion, well worth the money i mean. You make millions with the shop permits and you dont need to loot anymore with a pet when he has the equips for :)

But maple story can be as fun without cash shop, cash shop items doesnt change the gameplay, only your look. So even if you dont look as nice as other people its not important since your gameplay wont be affected.

Meh maple story is boring with or without cash xD. Get friends to talk with you so you wont get so bored.