Sausage is meat, just ground up. People use the term “american cheese” to refer to a variety of products, ranging from almost all real cheese with a small percentage of emulsifier added, to shit like Kraft singles which is mostly milk protein concentrate and emulsifier with a small percentage of real cheese added (allegedly). The latter is usually labelled “pasteurized process cheese food/product” or something similar, US law forbids actually calling it cheese if the cheese content is less than 95% iirc