I like programs like WW and 12WBT because they reinforce what to eat, what good for choices are, what foods are nutrient dense but calorie light etc. They're more around education rather than just weight loss. That being said, if you're not someone who works out, 12WBT will be hard. Possible, but hard. I'm finding the WW workouts super easy, so I'm adding extra weights and reps to make it more worthwhile, but I'm fairly fit and go to the gym regularly (usually) so I know how to manipulate it to suit me. I'm finding the biggest incentive for me is that I've paid for a program so there's an obligation to follow through. It might be worth speaking to your GP first to see what they think a good option for you will be based on your current fitness level and health.
FTR, I actually found 12WBT menus and recipes to be on par with how we ate anyway and DS1 ate whatever I served up (DS2 wasn't on solids at the time). Our diet was very similar so it was fine for us, it was more portion control in my case.
I've half-arsed done shakes twice before and hated it. I need to chew otherwise I feel completely deprived and it just made me irritable and hangry. Plus, because there was no financial outlay, I just stopped without feeling like I'd wasted money IYKWIM.
Good luck with whatever you choose.