For both Freeholds and Condo & Other properties, the lease term is a default filter. It appears in the filter menu for the Table, Map + Table, Map + Card, and Map layouts, for the Consumer Layout, it is found under More Filters.
For Commercial properties, find the Lease Term filter under Add a Field at the end of your filters. Select either Maximum Rental Term (Months) or Minimum Rental Term (Months) from the drop-down.