I need custom automation that updates the Title field in the Meeting module. I want to update the Title every time a meeting is created or edited with a custom value of "Related to - Contact Fullname + PickList1{Service} Value + PickList2{Service Details} Value"

I tried Actions>Field Update, but it didn't work.

I know how to set up a workflow with a function, but I cannot write the function.

Can someone help me with that? Thanks so much!