Hello Dear Anne thanks for support by answering our questions
Is it must to add land use to our model while using manually it was not displayed on WEAP i must convert it to vector first?

Dear Milko,
a) it is not required to input land use data to your model. The land use data allow more representative variability in other parameters--like runoff, infiltration, ET, etc.
b) adding the land use data as a GIS (vector) layer would be only for display purposes. What WEAP would want to know is how many acres/hectares belong to each land use class. These areas should be calculated in GIS and then input into WEAP.

Anne