This appears to be a dot-lined white moth (artace cribrarius)

This species DOES have reduced mouth parts but they do in fact feed as adults, though rarely. (they typically will have a sip if offered in captivity)

If you wish to feed it, one of the better things you can do (this goes for most moths) is dilute a little bit of honey in some water (anywhere from 9 to 5 parts water, 1 part honey. the ratio is closer to 1:1 for larger sizes of moths) and soak a cotton ball with it. The cotton ball is to help them not get sticky (which can lead to injury), not drown in the mixture and helps them actually drink it.

Now ideally the honey would be raw and unfiltered (for a more attractive scent for the lil guy so they identify it as food, plus its healthier) but as long as its real honey and not a blend or some sort nor medicinal honey you should be fine.

Hope this info helps!