Honestly, the leap from Year 10 to Year 11 was not very big from recollection. I don't think you have much to worry about.
Headstart is yet to come, do I study in the hols? If so, what should I do.
Some people feel it fitting to revise during the holidays, others don't. Depends on (a) whether you feel up to it and (b) choose to do so. Year 11 is really just a practise run for Year 12. Actually speaking, you just need to pass all the classes and have a good enough attendance rate to continue.
I've also heard that you should revise everyday, but I always slack off and have no movitation to revise.
This is false. Revising everyday, especially on days with zero motivation and no variation in how long you study/ studying too long can cause premature burn out. This is definitely something you
do not want, because then you'll feel deflated and lack motivation by the time you get to the final exams in Year 12. Instead, you should have some downtime and some days where you plainly don't revise. Back when I was in Year 11, I think I spent Friday nights resting and relaxing. You'll need time to recuperate from the week. Also, don't be afraid to socialise and keep your extracurricular activities/ life outside of school that keep you happy. You'll regret it more later, if you give them up.
If you have issues with productivity, maybe it's because you haven't:
- relaxed or slept enough/ taken a break in a while
- tried productivity apps like Productivity Owl, Habitica or Forest
- organised yourself e.g. to do lists, study timetables
- written out goals (literally on paper or having it on your personal device of choice is ideal)
- stayed much on AN - we usually motivate each other
- used methods such as the Pomodoro method
or sometimes you just have way too high expectations for yourself (Expecting yourself to work solidly for 10 hours non-stop, for example, is too unrealistic.)
I'm sure there are numerous productivity posts around the site. Search around and I'm sure a few of the other ANers can link you some.