What can you use to cover your shoulder and maybe arms while wearing a swimsuit and able to go swimming in?
You could wear a swim shirt or a tankini top to cover your shoulders and arms. You can also wear a fitting t-shirt that you can fold in a design and use it for swimming.
You can wear a swim shirt.
any shirt other than jean cut offs
A swim shirt or wetsuit try looking in Walmart for the cheapest
Usually lifeguards and other people at the pool don't mind when you wear a plain white T-shirt over your swimsuit. Have fun!