Hi there,
The change from A-level to university is a big jump. It's completely natural to struggle a bit with managing the workload and becoming a lot more independent with your learning. Don't beat yourself up comparing it as it really is a lot different and you will have a lot more now to do.
In terms of keeping up with it, there is no right way. The good thing about university is how much you can tailor it to what works for you. This may be daunting, especially if you had a system before which may not be working right now. Again this is all completely normal and I promise you are not the only one to struggle with university workload.
When I joined, i was recommended to spend 1 hour independently to every hour i spent in a lecture. This may mean you are already meeting such as your readings would be your independent learning and it's great your managing to keep up with the reading even if your revision is smaller, thats already a great step and commitment!
Honestly as a first year even doing 1 hour per day is already great and you should keep up the good work. But remember to also take care of yourself! It's okay to take a break to rest or pursue your hobbies. Make some time for any interests you have and join some societies to keep socialised! You won't be able to do your best work if you are too worn out,
Good luck with everything!
- Sophie (uni of Bath)