it depends on the individual (contracted) lounge policies.

Access: depending on what kind/calss of Priority membership you buy, you (and an accompanying guest) get access (you show your Priority card and you will be charged entry fees per person). I have seen children at such lounges, but I am not sure if they entered with a Priority Pass or another membership-card of that lounge.

Drinks: more often than not there is a 'help yourself open bar' in the lounge offering also a very limited wine selection and some spirits.

Food: may be some chips, bretzels, peanuts. More than that are very rare exceptions.

various: one or 2 TV-sets are running, in Europe there will often be an 'open ' smoking section, sometimes (paid) Internet access, TV-screens with departure and arriving informations, rarely a limited selection of newspapers and 'old' magazines.