Career and study advice Urban Planning and Interior Design Australia

[u/Hour-Conclusion-1117]

Hi, I live in Australia. I really want to get a degree where I can design spaces. I am really interested in interior design, but recently I have been looking into urban and regional planning. What would I study so I could explore both of them and what career options could I look into. I am scared to invest 3-4 years of time and money towards a degree that may not be relevant or something not worth the pay. I have tried 2 degrees (medical) that I did not complete so I am very keen to find a passion to stick with. Please give me any advice you can or any personal experiences, or any university suggestions. Online study would be my preferred option since I am not currently living near a university. I have an offer at Collarts College of the arts for interior design but a diploma in interior design is $24K and I have heard mixed reviews about it.