Unencumbered properties have no mortgage or borrowing secured against them.
If you inherit a home without a mortgage, you might decide to:
Live in it.
Sell the property.
Rent it out.
Remortgage it to raise capital.
Most lenders will need you to have owned the property for at least six months to offer to lend. However, you can find a mortgage much sooner by working with a specialist broker who can recommend mortgage providers who offer Day One Remortgages or similar products.