Just stop eating red meat makes the 70% of going vegan in the greenhouse gas department if I recall correctly.

So if you still want animal products just reduce or stop eating beef and that would do a lot.

Some source as reference https://woods.stanford.edu/news/meats-environmental-impact

I might have underestimate how much difference there is between beef and other animal products. Between methane and land usage they might pollute an order of magnitude above other meats.