I just started this game and have a few questions.
What are the smelting stones for?
Where do i get a pickaxe to mine?
What is the best class?

Thanks

You will get a pickaxe when you reached a lvl, it will be automatically go into your inventory.

There's no best class, it depends on how you use them.

When i gain a combat level? or a mining level?

When i gain a combat level? or a mining level?
u'll get it at some quest at ur lower lvls.

or you could buy it at Merchant Geres.
which is located in the town