
Certified GKH Gardening Expert
The Corn Palm is not, actually, a palm at all! It is a type of Dracaena. Those mushrooms are Leucocoprinus birnbaumii. They are toxic to consume, but are quite beneficial to your plant. They consume dead and decaying material in the soil, and their presence makes other, detrimental, fungi not able to get established in the soil. These mushrooms produce mycotoxin that keep other invaders away, while helping to break down material which will feed your plant, in turn.
Do not remove them.
I would advise watching your water, though. I noticed that the container does not have a drip pan, and likely no drainage. This will be a recipe for disaster if you don't keep a careful watch on watering.
Because of the size of the container, and volume of soil within, I would advise getting a moisture meter. This will tell you if there is moisture in the soil. You want the meter to read "dry" down just a little further than the half way point of the container before watering again.
This will be impossible to eyeball. It will require, either, a meter or weighing the container completely dry vs fully saturated. I prefer the former.
Here are some articles that will help:
https://www.gardeningknowhow.com/garden-how-to/soil-fertilizers/testing-moisture-in-plants.htm
https://www.gardeningknowhow.com/houseplants/dracaena/how-to-grow-dracaena-corn-plant.htm

The planter does have holes on the bottom and I even put an insert in the planter so I would not need as much soil when I replanted it....???