http://destiny.wikia.com
I use this site to check exotic bounty steps, weapons specs, etc.
Basically for now just go with the story missions and do as much bounties as you can. Doing bounties gives you Vanguard reputation (and exp). You need level 2 to buy armor, and level 3 to buy weapons. Also there are Crucible and factions reputations, but they require Crucible marks. Don’t bother with them before getting to level 20 and Vanguard reputation level 3. Keep in mind that when you return finished bounties they give you exp for your char and your gear, so have whatever gear or subclass you want upgraded equipped, before cashing in the bounties.
Also don’t bother upgrading gear too much. Save you materials for purple (legendary) items and dismantle everything white, green or blue that does not work for you. The goal is to get to level 20 after that you level up by getting items with “light” stat on them.
If you have any questions just ask!