I started with Stronglifts 5x5. It's a good starter program if you haven't lifted before, because it'll give you the opportunity to drill and learn the movements, and the program is simple, and there's an app that holds your hand.

In terms of programming, it has some deficiencies, but most people just need a structured program to start with. You can probably run it for 12-18 weeks and then have a strong foundation to switch to another program. People argue its deficiencies, but if it gets you started and gets you structure to build a routine with, that's what you need, IMO.

For the last couple of years, I've been training with Jim Wendler's 5/3/1 program, and it's fantastic. I keep getting stronger and can probably happily train on it for many years to come. I've competed in a couple of local powerlifting meets, and have a routine that I feel like I can sustain forever. There is a 531 for Beginners program, too, but it's less hand-holdy than Stronglifts.

5x5 is a simple and effective program. It's gone the route of marketing and sales but the principle is the same. A few big lifts a few times a week produces a lot of strength. You'll be surprised. You don't need to do 50 exercises.

5x5 has already been brought up a bunch of times. Starting Strength: Basic Barbell Training was a good book for me to cement each lift and I picked up 5x5 later for the routine. SS is a bit long-winded, it only covers a handful of basic lifts but dedicates a chapter to each one. Proper form is really important in not hurting yourself and maximizing your time in the gym. Being thoughtful about which muscles are getting activated and getting comfortable on how to position yourself really helps when the weight goes up.

The New Encyclopedia of Modern Bodybuilding (Arnold Schwarzenegger) I remember half was life story and theory on bodybuilding and the latter part was a good reference of a bunch of variations on exercises to mix things up.

Both of those books have been around forever and are generally well regarded. Your library probably has a copy you can borrow.

Here’s pretty good starting point for building overall strength: https://stronglifts.com/5x5/

My opinion is the best strength training routine is the one you can stick to. Sometimes you get into a routine because someone told you it's the way to do things. You try to force yourself to do it even though you don't like it. Eventually you stop doing it because you're not motivated to do something you don't like. At that point you might think, "if this is the way I'm 'supposed to' workout, but I don't like it, then I've failed and just won't workout because anything else is not the way you're 'supposed to' do it". Don't listen to anyone who says you have to do one thing or another. Do what you like because you'll be more motivated and stick to it.

This has been my experience... Personally, I don't like going to a gym. I'm not a fan of the atmosphere. I've tried several gym-based workout routines and I just never enjoyed doing them. When I say gym-based, I mean routines that really require gym equipment and access to heavier weights.

I also don't like workouts that waste a lot of time. I found with gym-based workouts I always had to keep looking up each exercise because I would forget exactly how to do them and that wasted a lot of time. There also seemed to be a greater risk of injuring yourself doing certain exercises, especially those requiring heavier weight. I also found exercise routines advertised as being "simple" or "basic" would have several exercises requiring equipment my gym didn't have, so I always had to figure out alternative exercises for that muscle group, which also wasted time.

I ended up doing P90X for a few years, which was great for someone like me that always has other things occupying my mind because I didn't have to think about what exercises to do. It was all laid out for me. Also, I could do it at home and it incorporates HIIT, which allows you to get in some cardio. As I got older, I found P90X felt like it was over-training and I couldn't keep up with the intense hour-long exercises. I switched to P90X3, which has 30-minute routines. That was good for a while, but personally not enough strength training for me. It had a variety of exercises (because variety is kind of the P90 way), but a lot of the exercises didn't really feel like they required enough exertion. P90X3 is probably good for someone starting out though if you need to get a basic level of physical fitness before moving on to more intense stuff.

After P90X3, I purchased RIPT90 Fit, which is very similar to P90X3 (30-minute home workouts) but is cheaper and has fewer, simpler, and more impactful exercises that I think maximize your 30-minutes. I still occasionally mix in some P90X3 routines, like yoga and core workouts.

HTH

What are your goals?