Hi
So just to start, asking more than one question per post is not something we prefer.
1) we dont get credit for answering multiple questions
2) it does no benefit people who are searching for what could be your 2 or 3rd or 6th question that is completely irrelevent from question 1
Our goal is to make it so that people can search and find existing answers so they can get done quickly. But multiiple questions pre causes that to not work well.
1) Yes you can easily create a flow that runs every day (or however many times you want) and it can check your flow and send a reminder.
-however in this case you should use Sharepoint or excel to Track whether you already reminded them that day, so you don't spam them.
1. You would have a scheduled flow trigger
2. Then a List Rows in a Table (for Excel)
--add a filter, where the column is null
columnname eq null
you may hace to use blank() possibly depending on the field type
3. Since your filter should only return ones you want to report on,
Add an Apply to each
the input should be the Dynamic body/value property from step 2
inside the apply to each, you can check your Log list, to see if you already email them by doing a get items (sharepoint) or list rows (dataverse) etc etc
Inside the apply to each after you verified that you are supposed to send it, send your email
Make sure your email addresses are configurable somewhere, again sharepoint, or other Excel
If you want, instead of simply sending an email because you haven't yet and the daily check just triggered, you can use other fields in the Excel to do conditions like, is it close to a deadline (now that time period would have to be someone in a list etc)
So the answer is yes, and yes to the rest, I gave you a solid basic outline thats the answer.