You really need to do some research and stop asking such generalized/broad questions. TRT is not a one-size fits all protocol. First off you need to get blood work done to establish you have low testosterone, then you need to start a treatment protocol. Now that will all depend on how good/knowledgeable your doctor is as to how you are treated. As for your question as to 'what's the maximum dosage', TRT is very individualized, so the maximum dosage is the dosage required to get the individuals testosterone to the optimal level whilst minimizing any negative side effects (such as elevated estrogen levels). For some people this is 250mg Test a week, others it's 80mg. It all depends on the individual and how they metabolize the exogenous testosterone.