4:35 PM, Monday February 27th 2023
For your first question, I would suggest you restart as the lesson material has been updated and maybe take a look at the critique you received. Even if you got it 3 years ago it could still help you understand the material better.
For your second question, it helps to see the lessons as puzzles to solve or goals to achieve. I finished drawabox in about 6 months and I never really felt burnt out while doing it. What really motivated me was setting the official critique cooldown as a deadline for me to finish the work. Even though uncomfortable recommends against this, as long as you do the best you can, following the instructions to the letter and incorporating the feedback you receive from official critiques it is doable. However in your case I wouldn't set the deadline for 2 weeks. Instead set it at a reasonable time which you can expect yourself to do it by. This makes deadlines a great way to stay motivated and finish the course.
But avoiding burnout would be the total opposite of setting deadlines. You avoid burnout by going at your own pace and setting reasonable expectations. The majority of people who do drawabox give up by the box challenge and claim they're "burnt out" from doing boxes. But that's because all they did was draw boxes without doing anything else. Which is why the 50% rule is crucial to avoiding burnout and in your case you could do something like a 30/70 "rule" or spend an even greater time doing the art you want to do, as long as it's equal or more to "50%". Doing this will probably make it less likely that you will quit.
So to avoid burnout and finish the course you have to find a balance between the deadlines you set and the amount of time you spend on your own art.
Finally I feel like the reason you quit in 2021 was more so due to getting "negative" feedback which is the best type of feedback to get. If you got feedback that only sang your praises it would be pretty useless if you were trying to improve as you would most likely know what you're doing right (although not always the case). I would suggest going over lesson 0 again to remind yourself of how the course works and how to handle feedback. This timestamp of uncomfortables video might help you handle feedback better by changing your perspective to not take your work too seriously.
Hope this helps, if you have anymore questions feel free to ask.