The Old and New Testaments are both valid excluding animal sacrifice for absolving sin because Jesus was the ultimate sacrifice for that.
ALL PEOPLES should follow the diet in Leviticus 11. Why? The Father knew man could easily poison the flesh of animals that clean the Earth and waters (ie. pigs have no sweat glands thereby allowing microtoxins from injections and the garbage they eat to build up in their flesh which is then infested by those not respecting this diet).
Also, ALL PEOPLES should even be keeping all the Old Testament Feasts (literally translates as “Appointed Times”).
The New Testament does not replace or nullify the Old Testament.