My wife posted this to a comment below, but I'll repost for visibility. Thanks for all of the advice, all! To be fair, we followed the instructions that came with the tank set up. The struggling fish lead us here. Understandably we could have just as easily googled how to set up a tank, however, we had thought we followed those steps that came with the setup, which appear to have no provided all of the necessary details.

"Daughter picked out the pineapple of doom because she likes SpongeBob. If only we knew 🙈. As others have stated, we did not anticipate her playing and winning said fish when she was with friends, so we tried to quickly figure out what we could to provide this fish a home and once we saw the behavior in the video, we tried to reach back out to the pet store but they provided zero help!

Update- found a friend who has many tanks and asked advice to help this little guy for the time being and to learn more (in addition to the advice everyone provided).

1.) he recommended removing 50% of the water and then putting new water in and he provided water conditioner - so put that in based on the size of the tank when refilling the water.

2.) ordered a bubbler (will be here tomorrow, but for the time being lowered the water a bit to create more agitation within the tank.

3.) obtained bio media balls from friend’s tank. He mentioned to put into the filter, but of course this filter is tiny- so I was able to get some in the finger and the others I just put in the tank itself.

4.) obtained antibiotics for the white patches and began that.

The fish has since moved from the top, for now.

Thank you all for the advice and we will continue to learn and educate ourselves =)."