But my problem is when I receiving my products, in the odoo 13 I don't had this problem.I received the products and they going to the location and I reserved my products in the time I need. 

Now every time I received one PO I need check the forecasting to see each orders waiting for this products and separate the products after I received because the product put automatically the quantities inside this orders.

This automatically allocation between my PO and the sales order I want to change like I had in Odoo 13, it's possible ? 

Hi,

Checkout this app: https://apps.odoo.com/apps/modules/13.0/mto_required_stock

Hello,

Odoo provides reservation of stock only after confirmation of Sales Quotation. 

This implies that stock can only be consumed in shipments related to the Sales Order. 

Some businesses might need to do stock reservation from the Sales Quotation, as they want Quotation’s impact on Forecast Inventory for Reordering Rules. 

There is one ready app available in odoo store Stock Reservation at Quotation.

By using this app, you can reserve stock of items added in Sales Quotation.

Here is the some highlights of this app.

=> Warehouse specific stock reservation configuration

=> Reserve Stock manually at Quation Stage

=> Auto stock Reservation at Quotation is Configurable

=> Option to release reservation

=> Adjustable with change in Quotation

Click here to know more about this app

Default behaviour: Stock is reserved as soon as the sale order is confirmed and the delivery order has been checked for availability.

If you want to change this behaviour, I think you have to create your own module, and when you execute 'confirm order', do the things which happens when you do check availability of the delivery order.