Hi,

To set an alternative courier service in Odoo, go to Inventory > Configuration > Delivery Methods, click Create, enter the new courier's details, configure the pricing, and then save it to use as a shipping option.

Hope it helps

Hi,
You can add the shipping methods not available in odoo by following the steps provided in below link.
https://www.odoo.com/documentation/17.0/applications/inventory_and_mrp/inventory/shipping_receiving/setup_configuration.html