What colors make green?

Blue and yellow make green. Equal parts give a mid green; more yellow pushes it towards lime and more blue towards teal.

Add white for a lighter tint (#80d499) and black for a darker shade (#00651f). Add either a little at a time - both shift a mix faster than you expect.

If a green looks too loud, add a touch of red - its complement - rather than black. Black tends to turn green murky and olive.

No. Screens mix light additively, so red and green light make yellow there. These results are for paint, ink and dye, which mix subtractively.