@arc90901 I see there's a lot of the same complicated or time intensive advice that always comes up for this. I don't know why it's so hard for good information to overcome bad information.
You don't need to stretch every day. You don't need to do a bunch of exercises. Both of these guidelines are low compliance and will be hard to maintain, and following this advice is why most people never get very flexible. They will certainly work if you have a lot of time and self-discipline.
When I was a kid I got that President's Council Youth Fitness Award, but the only test I didn't pass was the sit-and-reach. I was embarrassingly bad at this. It makes sense, my dad can barely get his hands past his knees and my mom is very unlimber for a woman, also. One time in PE, my teacher yelled at me for not reaching during warm-ups, and I had to protest that I
was reaching! Well into adulthood, I still couldn't come with 8 inches of touching my toes.
However, I was able to touch my palms to the floor within 2-3 months by training once a week:
With a heavy dumb bell or kettlebell from your hands, and straight legs, bend over until the weight touches the ground. You should feel a nice painful stretch in your hamstrings[1]. If you don't feel this, stand on something. I use stackable pads.
I did 1-3 sets in a session, once a week. Each set, I would do as many as many as I could or had motivation for. The next day, your hamstrings should be quite sore.
I use a 53 lbs kettlebell. My 67 year old dad uses 18 lbs. You'll just kind of have to guess at it, but I wouldn't use anything more than 1/3 of your estimated 1RM, and I'd start with well under, to protect back health[2].
Each week, stand on something a little taller. That's how you progress your flexibility.
[1] Don't be an idiot, but actual flexibility performers will tell you that pain during stretches is fine. Almost no one has the pain tolerance to damage anything. Your body will guide you. If you go to "gentle stretch" then you need to do a lot more sets and progress will take longer. I trust my judgment, but I can't speak for you.
[2] By the way, a side benefit of this exercise is strengthening the lower back. When I started training my dad, he'd had chronic back pain for 30 years. Within a few months, his back pain was 100% gone. People will throw a lot of fear your way about shear forces on the back, but you can't make a strong back without stressing it. Strengthening your back for compression forces does nothing for strengthening it against shear forces. Use enough weight to stress your hamstrings and back, but not more than you can handle confidently. Use more reps, not more weight. Use your judgement.