Q.Potatoes
When I harvest some potatoes can I put back mulch and soil together to grow more potatoes?

Certified GKH Gardening Expert
You can harvest a few potatoes from a potato plant and leave other on the plant to get larger and for some smaller potatoes to develop as well. But, this will only happen if you leave the potato plant largely intact and only harvest a few potatoes at a time.
If you pull up the whole plant and remove the potatoes and replant the plant, it will likely die and if it does not, it will not have the time or energy to grow more potatoes before them end of the season.