Loads of good ones to choose from, mate. Personally, I like the original 5/3/1 by Jim Wendler, and WS4SB part II by Joe DeFranco.
Depends on a few factors though, like how often you can train, the sort of training you like to do, etc.
How many days a week are you looking to commit to?
Starting Strength is a good program to get lots of practice on the main lifts but don’t fall in the cult that is 5x5. And watch for the elitist and smart alex comments that a lot of coachs employ these days - Rippetoe is an very good example. Why can’t they just relax and talk like real men?
I’m 50
Waterbury, three times a week was a godsend for me. I also do some kettle swings on the off days. Just to keep the groove.
Yeah i used to follow waterburys old stuff a lot. He was the first guy that introduced me to 10x3 which is my favorite rep/scheme for strength and size.
His Total Body Training and Rep/Set Bible articles are good reads.
Soild training programs however i don’t use so many varations anymore like he recommends and neither do i change rep schemes so often.