Thanks for the answer, need more clarifaction on it, intially when we are creating the blanket order, we set the quantity of a product. so what is the use of that quantity somehow everytime when we are crating FRQ , we are updating that.

also, in blanket order, can we order different product everytime we are creating a RFQ, or we can only onder same product added initilally in the agremment?

As you mentioned we can set the quantity of the products inside the blanket order and it will be shown in the quotation by default. and also you can make any changes in the quantity if you need.
The Blanket order can be customized By selecting the agreement option you can see the option for "Quantities": If one needs the purchasing quantity similar as stated in the agreement, It will be possible by choosing the option Use quantities of agreement. And if one needs to choose the quantities manually then it can be accomplished by selecting the Set quantities manually.

And also you can add different product as per your need not only that added initially in the agreement. But by default, the products that you added inside the agreement initially will be shown