form and sub form (Filter)

thank you
I have form (master) and sub form
Question No (1)
How can i make ((Filter)) to the (((sub form only ))) Notes: I don't want
the master form included in the filter only sub form Filter
**** using command button in a main form ((master form))
Question No (2)
How can i apply a filter to the ((sub form)) after selecting the condition
in the sub form
**** using command button in a main form ((master form))
Question No (3)
How can I remove filter sort from the sub form
**** using command button in a main form ((master form))