An atom has a charge of +1. if the atom's nucleus contains 23 protons, the atom must have

If an atom has a let's say, +2 charge, it will mean that the atom has two more protons than electrons. Protons have +1 charges and electrons have -1 charges. So, said this, if you had one more proton than an electron, it would be a -1 charge. Because of this, if an atom had a +1 charge, it would have to have one more proton than electrons. So, the answer could be "the atom must have 22 electrons" but, the question is sort of vague? It could really be anything.

22 electrons (electrons have -ive charge)