Procedure for commercial activities

Answer:
ISO 9001:2015 has no mandatory procedures. Please check clause 4.4.2 a). It is up to each organization to decide which procedures are needed to support operations.
Most organizations decide to develop procedures to describe how processes should be performed, and work instructions to describe how specific activities should be done.

A commercial procedure could be one that describes how requests for quotation are received, treated and proposals elaborated, approved, sent, negotiated until an agreement is reached.

The following material will provide you more information about commercial activities:
Article - List of mandatory documents required by ISO 9001:2015 - https://advisera.com/9001academy/knowledgebase/list-of-mandatory-documents-required-by-iso-90012015/
ISO 9001 document template: Sales Procedure - https://advisera.com/9001academy/documentation/sales-procedure/
[free course] ISO 9001:2015 Foundations Course - https://train ing.advisera.com/course/iso-90012015-foundations-course/
- book – Discover ISO 9001:2015 Through Practical Examples – https://advisera.com/books/discover-iso-9001-2015-through-practical-examples/