@Ximena-and-Mauricio0 You definitely need to talk with a tax professional, if only to have him set you up so that you know how to handle your rental business going forward.
The IRS website has instructions for the various forms -- Schedule C versus Schedule E, etc. but it can be heavy reading -- I have numerous properties. Some are filed with their own tax returns as they are entities with tax ID numbers and some are filed on my personal tax return on a schedule E as pass-through income.
Talk to a tax professional.