Thermophilic is a heat-loving culture. It is used for cheeses that must be heated to a higher temperature such as mozzarella, parmesan or Swiss and Italian-type cheese. Yogurt is also made with a thermophilic culture. Mesophilic is a non-heat loving culture which would be destroyed at higher temperatures. It is used for 90 percent of your cheesemaking.
Buttermilk is made with a mesophilic culture.
I often used these items as culture substitutes in some of my recipes. You can control the temperature better by adding more or less hot water as needed. This isn't real cheesecloth, and it won't be useful for draining anything. Cheesecloth is a much thicker, muslin type 100 percent cotton. It can be washed in hot soapy water with bleach and be used over and over again.