what to look up

Hello my beautiful people , I hope you are all doing well. A couple of days ago I received my dad’s results positive of cancer. ( 55, had a PSA of 5.8, biopsy confirmed 2 3+3=6 and 1 3+4=7 ). my dad’s appointment is on tuesday and he doesnt know yet as i cant break the news to him. Meanwhile, ive been talking to a couple of people while trying to research all the treatment options. I personally dont think he should go for surgery but I want to make sure I help him make the right decision. It says its grade 1 and 2 so maybe AS would be recommended but knowing him he’d want to start treatment now rather than wait. What are some things I should consider , what can i look up specifically to find information? Currently Ive been looking at brachytherapy, RALP, cyberknife and so on. I will ask the MD for a PSMA pet scan, i also know there’s a test to see how aggressive or fast moving the cancer may be but i cant seem to figure out the name. Are there any other test you guys recommend ?