In Theravada Buddhism, they eat meat as long as it is offered to them and the animal was not killed specifically for them. In most Mahayana traditions they have a strict vegetarian diet. However, the Buddha did not ask his followers to be vegetarian, nor was he a vegetarian. Many Buddhists are vegetarian simply for the act of compassion towards all living beings.
“But the animal is already dead, so how did you contribute to killing it?” is a question that comes up often. Think of it as a “supply and demand” approach. Yes the animal is already dead, but if you didn’t contribute to buying it, then there’s one less animal that needs to be sold. The less you buy, the less the supply for more meat will be needed, which means less killing of animals.
Simply put: No. Buddhist don’t have to be vegetarian.
Smile and be well!