What's a hobby that actually takes up time?

I'm a business student so I have a lot of free time. However, most of my time is spent just scrolling on the internet or watching YouTube. I have hobbies like Horse riding, reading, birdwatching, etc. But all these things just take one hour out of the day. After doing them I'm back where I started having free time again. What are somethings that can actually take time out of my day?