Opportunity Closed as Won process

Hi, if this is a stupid question, please bear with me as I inherited our CRM setup from an ex-colleague without documentation or training.   I do not know which processes are default and which were set up by said colleague.

We have a work process for Opportunity Closed As Lost. 

My question:  Is there a default process somewhere for Opportunity Closed As Won?  I would like to add in an extra step so that when Opportunity is Closed as Won, the field "Relationship Type" in the respective Account is updated automatically to "Customer".

Thanks

Nicole