I can't really add anything different than what others have said.

It is likely with spread to the spine that your father may be in continuous ADT.

With modern PSMA imaging and the advances in radiation planning and delivery, SBRT may be able to treat his spinal mets.

Likely his medical team will want him on ADT and an ARI. For the ADT, lots of choices, Orgovyx is one. There are still the side effects, hot flashes, muscle and joint stiffness, fatigue, genitalia shrinkage, loss of libido...though those on this forum and others say they are "less severe." I just completed 12 months, combined with SBRT to the single PLN identified in the PLarify scan, my sensing is yes, less severe, but that's a qualitative, not quantitative judgement. Hot flashes suck.

Still, while on treatment I changed nothing, most days went to the gym, took vacations to Oregon, the Great Sand Hill Crane Migration in Nebraska, went skiing with friends in Colorado, celebrated birthdays, anniversaries, rode with my sister in the Garmin Unbound 50, a 50+ mile gravel bike ride in the Flint Hills of Kansas near Emporia,

My medical team can and does a lot for me, what they cannot do which are useful in mitigating the side effects of treatment:

Exercise
Diet
Managing Stress.

Kevin