Off course you're not supposed to buy your own chestwebbing. When (if) you get to start training the army will send you a letter a week in advance, saying what you're supposed to bring (you can find the list on
http://blog.seniorennet.be/cbos/). Anything else will be provided.
On your first day, your cadre will also tell you what sort of stuff of personal purchase you're allowed to have. We were allowed to have the old model ABL boots, a petzl, a leatherman, NTGS-gloves & a wool cap (on the condition that we all bought the same one); but it differs from platoon to platoon...
ie.: some other platoons were allowed to wear srarves/buffs (scarf = no need to paint your throat/neck), and some others weren't allowed to wear different boots.
I'm talking CBOS now. GPO might be a lot looser, or a lot stricter, depending on the unit (either way, you won't be making good first impressions if you arrive at your unit wearing irregular boots & carrying 3 bags of sh
it). After GPO you're "bij wijze van spreken" allowed to do whatever you want (outside the wire).
Concerning applying for NCO or not:
it's not for me, not yet anyway, I might change my mind in a couple of years...
Keep in mind that you'll probably be leading people that are older and more experienced than yourself. A 28-year-old kpl. with 10 years in the army & 5 ops won't accept a 19/20-year-old sgt. with no real experience right away, it would take some time & social skills.
This isn't insurmountable though, and I'm by no means discouraging you to try it, I'm just saying it's more than just getting paid a little more...