Where are you getting this from?
My own experience. I’ve went down that path and it only lead to struggles until I started charging.
There are loads of professionals who do this sort of thing to get started. It’s just not in web design.
Please go on. Usually those professionals will already have a salary (low) and work on commission based on bringing clients in.
There aren’t many costs involved either, other than your time.
Hosting, domains, design tools. I forgot those are all free.
Make sure to read my last paragraph. I agree with Allen that word-of-mouth is valuable. But doing it for free in the process will not get you the clients you’re probably seeking.