How many covalent bonds can be formed from an atom?

Answer 1

It depends on the element

Following what one might call "normal" valence an atom such as carbon can form up to 4 bonds. But in some compounds, such as sulfur hexafluoride and atom can bond with as many as six other atoms.

Answer 2

The number of covalent bonds that an atom can form depends on the number of valence electrons it has. For example, carbon can form up to four covalent bonds because it has four valence electrons. Oxygen can form up to two covalent bonds because it has six valence electrons.