One should start with a single hobby. Indulging in too many things at one time will drain you and soon you will lose your enthusiasm. You should also keep in mind whether you can afford your hobby.
For example, reading, writing, gardening etc won’t take much of resources and will be friendly to your pockets as well. But in case, you fancy scuba diving or skydiving then it can cost you huge sums. It is also important to not make a plan to pursue your hobby. If you love something, it’s always better to start it right away.
If you are confused about different activities and your liking for them, you can pursue them all at once. Soon enough, you will able to realise which one you love the most and which one you find cumbersome. Pick the one you are most passionate about and maintain some consistency in practicing your hobby.