Without being more specific, ie... sacrificial meats, pagan altar meats...then meat of certain animals were for food and others were forbidden to be eaten. These are listed in the Dietary Laws.
If you're talking about the King James version, you should be aware that at one time "meat" did not refer exclusively to animal flesh, but was more or less a synonym for "food".
That requirement is not in the Bible.
Meat Fruits and Bread
The word "meat" first appears in Genesis 1:29 (KJV).
God says do not store meat for more than 7 days
Not together, but consecutively. Genesis ch.18.
Daniel challege the people by not accepting the the kings meat.
Meat is mentioned 285 times in the KJV Bible, but the majority of these refer to general food or to flour. The flesh of animals is mostly referred to as flesh, but God also often calls all mankind, 'flesh'.
meat eating is not sinful, gluttony (over eating) on the other hand is. there is not a single passage in the Bible that says that the act of eating meat is sinful. so you could safely eat meat (without being gluttonous) and it would not be a sin.
Green is the first color mentioned in the KJV bible. (Genesis 1:30) "I have given every green herb for meat"
The man who was fed by the birds in the Bible is the prophet Elijah. According to the Book of Kings, during a period of drought, God provided food for Elijah through ravens who brought him bread and meat.
Lamb is mostly associated with those two things as it says in revelation in the bible
The same reason the Bible says all the other absurd things - it is wrong.