Ionic bonds are a type of bond formed with the attraction between oppositely charged ions to form a chemical compound, this type of bond will have a transfer of electrons, from the positively charged ion (cation) to the negatively charged ion (anion). Since this type of bonding heavily depend on the electronegativity of the elements, we will have compounds formed with metals, located more to the left in the periodic table, mostly group 1 and 2, and with nonmetals, more to the right in the periodic table, one example of this type of bond is Chlorine (nonmetal anion) and Lithium (metal cation).
Covalent bonds are a type of bond formed with the sharing of electrons between two elements with no big difference in their electronegativity, usually, we will see nonmetals in this type of bond, since their difference in electronegativity is not as relevant as the difference between metals and nonmetals, one example of this type of chemical bond is Nitrogen and Oxygen, 2 nonmetals that can bond together.
Metallic bond, as the name suggest, is a type of bond that will strictly involve metals and not nonmetals, this type of bond has many properties but the low electronegativity in general is one of these properties, one example for this bond is Gold and Gold
Therefore the answers are:
Gold and Gold = metallic
Nitrogen and Oxygen = covalent
Chlorine and Lithium = ionic