Do I put a cover on the pot of potatoes after they start to boil?

Placing a cover on a pot of potatoes boiling in water will achieve two results: It will slow down the water evaporation otherwise lost without a cover, and will also help cook the potatoes a little faster – as the heat will be retained and cooking temperature consistent:

https://idahopotato.com/dr-potato/best-way-to-boil-idaho-potatoes