Flows can run for a maximum of 30 days.
You can use the "When an item is created" trigger to send an email when the item has been created.
You might consider creating a Flow with a Recurrence trigger that runs daily to send the other emails. When the Flow runs, it can loop through your list looking for items that meet your criteria (30 days since creation, etc.) and take action as appropriate.
Please post here if you need an example.
Scott