sure
firstly the structure, it’s much different to high school - you only take 4 classes a sem (or 2-3 if ur at unsw) but there’s much more content packed in compared to hsc. in high school where you’ll take ~ a year to learn a subject, uni expects you’ll do it in about 3.5-4 months (or 2.5-3ish for unsw), so the pace is accelerated - do keep in mind though, you’re studying a specialised area so things will build on top of each other mostly. eg im studying math so the skills i learn are mostly transferable from one class to the next and it’s not like every class is something where i have to build all my skills from scratch. overall, i’d say the pace is just increased at uni but it’s nothing insane and as long as you keep up and don’t fall behind you won’t have a problem.
for assessments it’s actually much calmer than hsc as you have much more assessments with smaller weighting. typically about 30-50% will be weekly activities, which sounds scary at first until you realise that each weeks work is only weighted to about 3-5%. this means that even if you bomb a certain weeks quiz or whatever, your whole subject mark isn’t going to be ruined, so there’s much less stress placed on assessments - compare this to hsc where if you screw up one task then 35-45% of your grade can disappear and your ranking is ruined. also scaling and ranking is basically non existent at uni, so there’s less reason to compete with your peers and more reason to work together which is nice. additionally the writing style expected in uni is usually less bs than high school, just write straight to the point and communicate effectively, no need for the “hsc writing style” a lot of subjects in high school expect.
for actual class content, it differs for each degree obviously but usually for an undergrad (bachelors) degree you’re just dipping your toes into a lot of fields. for example if you are studying electrical engineering you’ll take classes on basic electronics, signals and circuits, radio communications etc. not to say you have a shallow understanding after leaving a class but you also realise how deep a lot of fields are, and you’re really just getting down the basics. usually class content will all be new to you as well, although like i said before it’s building off of previous knowledge so as long as you keep up its not too scary. im also studying ahead a bit just so im more familiar with the content for next sem but there’s no need to do that and as long as u spent the required hours there’s no reason you should fail a class
speaking of studying independently, a lot of people say uni is about developing these skills; i do think that obviously there is more emphasis on self study in uni, but this is mostly because you’ve reached a certain level of “maturity” in a lot of subjects. as an example i’ve already learnt proofs, basic linear algebra and basic calculus, so there’s nothing technically stopping me now from learning the rest of the subjects in my degree in my own time provided i had the hours. what i mean is that you kind of end up with the baseline knowledge that allows you to understand a good chunk of what’s in your field, provided you study subjects in the “prerequisite” order eg i wouldn’t study a 3rd year subject on a topic if i didn’t know the 2nd year subject on the topic. this is pretty nice, it pretty much just means that you’re only restricted by time and effort when it comes to learning stuff in your field.
also, the unis (at least uts but i know others do too) offer plenty of support and you’re definetly not completely independent- this ranges from peer support programs to tutorials where you can ask your peers and teachers for help to emailing your lecturer. you certainly aren’t studying everything by yourself and if you get stuck there’s plenty of ways to get help, so don’t get too worried that everything is “independent”
tbh i really enjoyed my first sem of uni, it was much more chill than high school lol but still a lot of new stuff to learn, just different attitudes and it doesn’t feel as stressful since there’s no one time atar score to worry about