Me and carbon are non metals, tin is a metal because is on the left side. This means we could do ionic and coavalent bonding.
helium is a metal but is on the left because it has 1 electron total
Each element is group ing different groups, based on their number of valence electrons. Valence electrons determens how reactive or who it bonds with. It starts at one in the left and it adds one each group to the right.