Hello, I am a student as well, so my advice might not be the best!
I think you captured the rhino's proportions and volume quite well!
What would elevate your skill would be to practise drawing basic 3d shapes! The legs can be simplified to 2 cylinders that each start thick and become narrower the more down you go.
The feet (I forgot the correct word) are like the front of an american truck!
With those shapes you will have a good foundation to add details on.
I also recommend trying out different brushes and see which one feels super nice to use, that will make your lines more consistent and fun to draw ^v^
Curvy lines look flowy & organic but they also represent indecision.
What I mean by that is that
when I draw something with a curved line, I am not forced to decide exactly where a line ends and another begins.
And so I don't learn as much.
What would help a lot would be to try and make every stroke count.
I recommend trying to only use as few straight lines as possible, that way you will always have to decide exactly what stroke you want to do and why.
If you make a mistake, you can look back at your reference and learn why you made that mistake, it personally helped me! c:
If you need to draw a curve or a circle, try and do it with as few straight lines as you can.
I really hope this is helpful somehow! .w.
A much much better teacher than me would be Ethan Becker on Youtube, I hope you enjoy the way they teach. Thank you for your time on reading this whole thing!
(As for Ethan Becker, do not worry about the titles, noone is being dissed, the titles are a joke and Ethan is playing a character and is actually very wholesome c:)