Configuration:
Commission Plan

In Odoo, this can be achieved by installing Reseller Commission for Subscription app

Once Installed, you will be able to see new set of options for resellers and commissions in the CRM application.

Go to CRM -> Configuration -> Commission Plan and Create a Commission Plan

Give a name to the commission plan, You can set a default product that will be purchased when the commission gets applied.

Set the company, if you are in a multi-company environment and the commission is company specific.

On the lines you can specify how the commission applies, If the commission applies for a whole category select the category. If it applies to specific products within a category, then add the category and select product per line.

You can also add multiple product categories and products with the same plan.

Rate is where you can specify the % commission that will be applied.

You can also set a maximum commission per order, once you enable the capped checkbox.

If the Sale Order Template is Used, Only the sales order that use the specific quotation template will have commission calculated.

If the Pricelist option is enabled only, the sales orders that use this pricelist will calculate the commission.

Commission Product

Setup the proper expense Account on the Commission product, so that when it is used it will hit the proper commission account.

Partner Level

Go to CRM -> Configuration -> Partner Levels

Create a New Partner Level Called Salesperson and set the commission plan on the partner level.

Salesperson Configuration

Select the contacts that are linked with the salesperson.

Under the Partner Assignment tab, Select the Partner level as Salesperson. The default commission plan from the Partner Level will automatically be added. This can be changed, if the salesperson follows a different Commission plan.

Workflow 

Sales Order

When creating a Sales order, Add the Salesperson as the Referrer on the Order.

Add the Product/s that is part of the Commission Plan and the commission will be calculated based on it.

The commission rate can be seen on the bottom right corner of the sales order under the total. 

Invoice

Create an Invoice and register payment for the sales order.

RFQ

RFQ will be automatically created when the Payment is registered against the invoice with the salesperson as a vendor with the commission product that is set on the Commission Plan.

The value of the commission product will be the same as the Referrer commission.

Bill

Create a Bill and the corresponding expense Account set on the product will be hit.

Once the payment is made to the salesperson a payment can be registered on the bill.

Please review the Below post for Reporting on Commissions

https://www.odoo.com/forum/help-1/how-to-report-on-commission-259244