"Usually, meat is red."
Translation:Normalerweise ist Fleisch rot.
In German if you put adverb at the beginning of the sentence, there's no comma after the adverb and the verb in the second place. It doesn't matter if there's or isn't a comma in an English sentence.
Normalerweise trinke ich Tee mit Zitrone. Gewöhnlich gehe ich einkaufen am Samstag. Hier kannst du frisches Obst kaufen.
No, it is not. In German you usually don't separate adverbs from the rest of the sentence like you often do in English. And if you include the "gewöhnlich" in the sentence, it takes the fiorst position, so the verb needs to follow immediately: "Gewöhnlich ist Fleisch rot".