If you have time after bulding your shack try to find sheep and collect three pieces of wool by killing the sheep. (Or if you found iron while mining just smelt some in a furnace and make shears.) Then make a bed and you can sleep in it to skip the night. If you don't want to sleep then you can make more tools or even go out monster hunting if you wish.
Once you survive the first night in Minecraft all you have to do now is explore the rest of the world and make it your own.
If you don't know all of the recipies in the game here's a site that I found helpful. Minecraft Crafting Recipies
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