Suppose you discover a new element with 120 protons and 2 electrons in its outer level. in what group does this new element belong

Regardless of how many protons this element has, it has 2 valence (outer) electrons.  On the current periodic table, this element would go into the second group.  If you want a more specific answer, try alkaline earth metals, or Group 2A.

To create an ionic bond, 1 or more metal atoms lose their valence electrons to 1 or more nonmetal atoms, which accepts these electrons to complete their valence shell (the metal atoms also "complete" their valence shell by losing the outermost electron shell after they gave away the electrons, to reveal the full electron shell underneath). Therefore, the metal atoms becomes cations (positive ion) and the nonmetal atoms become anions (negative ion), and the force of attraction between opposite charges brings them together to form a ionic bond.