Help Needed: Salesforce Automation for Task Creation and Assignment

Hey community- I have a novice Salesforce Automation question, and the tutorials on Trailblazer and YouTube do not match my screen options. Anyone willing to lend a hand to tackle "Automation for Task creation when an Opportunity Reaches a Certain Stage and Assign it to a Project Manager user"? The assignment to someone else is my stumbling block; everything else is created. Thanks!