I agree with @saiyan - if that is your first time stacking steroids, better opt for something else. Trenbolone is extremely potent, and it has very tricky side effects, so you need to make sure that you know what you are doing, and it would be great to have a nice foundation first.
In any case, if you will insist on running trenbolone, I would not use more than 400 mgs, because it is extremely potent, 5 times as potent as testosterone to be precise, which is a lot. You would need to run aromasin for estrogen, cabergoline for prolactin. I would also suggest you to add in there some Cardarine GW, as it has a time proven ability to greatly reduce many of trenbolone's side effects, and it definitely helps with the lack of endurance due to trenbolone use.