You are eligible for visa free entry
You get 90 days within any 180-day rolling period - and that count covers the entire Schengen Area, not just Romania. If your trip takes you through Spain, France, or anywhere else in the zone beforehand, those days come off the same total. Plan your itinerary with that in mind.
Your passport is the only document Romania will accept - the DNI that works so well within MERCOSUR doesn't apply here. Your passport must remain valid for at least three months beyond your planned departure from the Schengen Area. Airlines will catch this at check-in before you even reach the border, so check your passport's expiry date well before you book anything.
Three months beyond your departure date is the official requirement, though having six months remaining is always the safer position when travelling internationally.
Must hold at least three months of validity past your planned return date. Have at least one blank passport page available for entry and exit stamps.
A return ticket or any confirmed booking showing you're leaving within 90 days. Officers don't always ask, but when they do, having it on your phone or printed saves an awkward conversation at the counter.
Hotel confirmation, rental booking, or your host's details with a full address. A forwarded email or screenshot is fine - nothing needs to be officially stamped or printed.
You may be asked to demonstrate sufficient funds to cover your stay through bank statements, cash, or credit cards.
Not a legal requirement, but healthcare in Europe isn't cheap for non-residents. Sort it before you leave - it's one of those things you won't regret having.
Check if you need a visa for your next destination