English Translation
I love parties.
The normal word for party is impreza, or more rarely melanż
Przyjęcie here makes no sense in my opinion and is a mistake.
I think przyjęcie is correct. Impreza can refer to an event, not only to a party, e.g. Impreza inauguracyjna Polskiego Stowarzyszenia Łownictwa Leśnego. Przyjęcie can be a house party (more common to say domówka), birthday party (przyjęcie urodzinowe or impreza urodzinowa) or wedding party (przyjęcie weselne). It’s more probable to find przyjęcie in a book set in the first half of XX century than in the modern day, though. Melanż is a party as well, it’s a common word among youngsters.
I’ll just add that “melanż” is more of a slang word (see the dictionary of Polish slang) implying that there will be a lot of alcohol - “przyjęcie” doesn’t necessary imply that.