Populating Date field if two fields match

So the trigger would be the creation of the new record. You would probably do it on 'Record Added' and in it, you would need to include all of the fields that you intend to query / search on. 

Your next step would be a 'Search Records' - you want to check to see if there is a previous record that has the same criteria/match. You would set up the search to look for records that have the same topic/coaching, and then include another criteria that the Record ID# is not equal to the ID from Step A- the idea being that you want to omit the current record from being matched too. You will want as part of this search to return the 'date' field that you're wanting to copy as one of the fields to use in later steps. 

Pipelines will automatically give you a loop associated with the search, and inside that loop you will do an Update Record action, where you are going to point it at Step A (the new record). The only field you need to map the the date from your search - so something like this as a mockup: 

*your field is named something different I imagine but the gist is there. 

Then that's it - your matched record will update your new record with the prior date.