While I agree that there is way more to "being healthy" than just not being overweight/underweight, I think it isn't a bad idea to approach this in the priority order. Solving the issue of being overweight is much simpler and much more impactful to the overall public health than trying to go after more rare and difficult problems.
0. https://www.cdc.gov/nchs/fastats/obesity-overweight.htm
1. https://www.cdc.gov/nchs/data/hestat/underweight_adult_15_16...
If your goal is to minimize the total number of health problems in your country, it would make sense to throw more efforts at a problem that affects 47 times more people, given that everything else about the problems is about equal. We are not comparing cancer to heart disease here. We are comparing two problems that are two sides of the same coin.
Everyone tries to compress a workout into a single time interval in the day, where you do n sets of each exercise and then go home. To do three sets in three minutes, you're going to have to pick a very conservative goal. Doing 5 sets spread out over the entire day, I could lift more and saw results pretty much right away, and really for the first time. I'd exercise while waiting for things like the drier to ding or toast to pop up, a file to download, a commercial break or a cut scene to finish. But, I had to have exercises I could do at home, which takes some creativity (or a lot of money).
Your body is conserving resources. The whole point of 'exercise' is to trick your body into thinking that you are an active person who needs to spend the extra resources to build and maintain large muscles, cardiac or lung capacity, or all three. If you are actually active you don't have to 'work out'. Your life is work, and your body adapts.
Once I got past that initial roadblock, I got results even from the gym, but I was able to be more consistent doing it at home.
The trouble with putting on a lot of bulk though, is if you stop. Exercise burns a lot of calories. Persistent exercise therefore changes your notion of what a 'normal' amount of food is. If you stop, it probably due to some major life event, and adjusting your notion of 'normal eating' might get lost in the mix. Which is probably why a lot of pro athletes chunk up when they retire (or get retired). Going from 3-4000 calories a day to under 2500 is quite a lifestyle change.
Pullups are the trickiest. At the time there was a staircase with open treads near my apartment.
For anyone interested in learning more about this, it's called "greasing the groove". There are plenty of web articles about it, and it's also covered pretty thoroughly in the book _Overcoming Gravity_ by Steven Low.
edit: Caution: don't start on squats without coaching.
It took 2 months of rereading the squat chapter, filming myself, correcting myself, etc, before I finally got that one down. Now that I understand it, I can spot faults in others, but it took a while for it to click. Rereading the dbook helps, though a couple of Rippetoe's coaching cues set me on the wrong path. A starting strength specific coach can straighten you out in just a couple of sessions. DON'T think any other certification, personal trainer, or coach is a substitute, they are NOT.
Don't do starting strength for a year. (If it takes you that long to do the novice linear progression, you are definitely doing something wrong.) Rippetoe's advice for intermediates is pretty marginal IMO and you can't possibly stay a novice for a year doing the program.
Switch to Barbell Medicine's "the bridge" instead of resetting the weights a second time.
That said, I recommend against people teaching themselves deadlift, because it's not nearly as intuitive, has more potential for injury, etc.
Another funfact is that you can literally go to bed for a few weeks, let muscle atrophy kick in, and lose more weight than any diet+exercise regime. Won't make you healthier, but you'll lose the weight. Yay metrics!