1. Assuming you are a U.S. citizen or resident. Any money or property you inherit, the receiver does not pay any tax. So there is no tax liability. The basis of the property is the fair market value at the date of death.
For more information read:
Your U.S. Tax Return: Tax on Inheritances
2. About business: If you have inherited the business, you must report profit or loss from the business on schedule C.
You can have loss for a long period, then IRS expects you to sell your business.