>>168443
>>168455
Depends what you're trying to do. Learn a technique? Draw from imagination? Draw from observation? Improve your efficiency/accuracy? These are all things you eventually need to do to get good.
A good place to start for any beginner would be to practice drawing from sight. You can do this for 5-10 minutes whenever you sit down to draw. Draw your hand in various weird orientations, or go look at things with weird shapes. As you improve try using a frame of video of some random person, or use nude references. Try to avoid capturing tons of detail, just go for the most important features, and try to get the relative positions and proportions of things close to the real thing. Focus on quantity over quality and don't worry about mistakes, but try to do it as good as you can in a relatively short amount of time. Don't go back to fix things, just move on. This develops two critical skills: hand-eye coordination and visual memory.
After that, you could make other exercises for yourself for things that YOU want to improve at. Drawing scenes with perspective, figures and poses, or anatomy, or mentally rotating objects. Take something out of loomis. Find some references, come up with something that is fun and challenging for yourself. Come up with 2 or 3 and maybe spend 15-30 minutes on them.
So that's maybe 20-40 min of exercises. If you only want to spend 15m on all of that, even that is better than nothing, and really you will get more out of doing this 10 minutes everyday rather than 2 hours once a week. Don't sweat this stuff unless you want to get really serious about it. BUT DO IT.
And then after that, doodle whatever and work on your general interests and techniques. As for what to draw, that is ultimately for you to decide. Draw some random stuff, and then try drawing a full scene. The complete process of finishing a draw from beginning to end, planning composition, execution, and polishing, are all skillsets in their own, so practicing them is necessary. If you find you are dissatisfied with your workflow in one area, try to come up with some exercises and focus on ironing out your biggest weaknesses first.