Do not be afraid. NASA has responded to some of the most important questions that people absolutely need to know about space travel.
Solid waste is collected in a container part of the hygienic component of the toilet waste of the space station, and these containers are thrown away during the destructive reintroduction of the cargo spacecraft. The urine is collected separately and sent through the distillation plant of the station's water recovery system, which helps urine convert from crew members to usable water.
No. Astronauts do not eat frozen-dried ice cream, but sometimes the cargo ship is specially treated for real ice cream. Sending ice cream is sometimes possible when there is space in one of the freezer pizzas on the way up, which will be full of scientific samples to return the SpaceX Dragon. It is normal for commercial supplies to deliver a small amount of fresh food to astronauts (usually fruits or vegetables), with ice cream occasionally making the trip.