I heard something to do with Nitrogen and …cow farts(?) I am really unsure of this and would like to learn more.

Answer -

4 Parts

• Ethical reason for consuming animals
• Methane produced by cows are a harmful greenhouse gas which is contributing to our current climate crisis
• Health Reasons - there is convincing evidence that processed meats cause cancer
• it takes a lot more calories of plant food to produce the calories we would consume from the meat.

Details about the answers are in the comments