you ever drywalled before?

If not, not to judge, but theres zero chance youre gonna skim coat the entire wall and get a lvl 5 finish (thats what a lvl 5 finish is).

anything less is not level 5, because that means your just feathering out the thickness introduced by the tape, which is then by definition, not a dead flat wall

Plus, zero chance your wall was lvl 5 to begin with, so you'll need to "improve" that too.

Id grab a 4" knife and some spackle, and smear it on the hole. Id sand it smooth, and repeat that 2-3 more times. by not using tape, you wont be building any thickness on the wall that requires much feathering. A .5" hole doesnt need tape anyway.

If youre not satisfied with the result, you can still slap some tape on there and proceed to attempt a skim coat if you want.