Ok then, your stamina gauge resets every 24 hours, it's up to you to know exactly what time that is, after your whole stamina gauge depletes, you can can't play in dungeons anymore.
At the same time of stamina, you gain back up to 3 revives, meaning, if you have 0, you gain 3. However, if you have two, you only gain back one, saying that 3 is the max without cash.
Obviously, you level up when you get to 100%, though sometimes I did get to 100% and not level up, mostly because I need like one exp left >_>.
You Menu has U as its shortcut.
Item Menu has I as its shortcut.
Skill menu has K as its shortcut.
Quest Bar has Q as its shortcut.
Friend bar is actually really called Party menu, has T as its shortcut.
Chat menu has M as its shortcut.
Options Menu has O as its shortcut.