Depends on so many factors, probably best to get some initial coaching.
I've switched to the 7/7 system routine used by Jason Momoa, who is a similar height and natural build to myself, and I'm doing well well off it, but I've been lifting since my teens so have nearly 40 years of experience and insight into what works for me. I'm doing alright, not as bulky as I used to be but still more lean meat than most 55 year olds...
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And a picture of Jason Momoa to compare...
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While not directly helpful you will find this article interesting and informative, particularly Peter Koch's comments about the value of resistance training as we age...
https://www.muscleandfitness.com/at...ife-bodybuilding-acting-and-playing-football/