I WILL not promote

So i create images as a hobby (its my main creative outlet) mainly for my stream or for my social media and i have people asking me on a semi regular basis for me to make them an image either based on their concept or just asking for one of my designs for whatever purpose and its happened often enough that i have recently decided to start looking into possibly selling my content or possibly producing apparel or merchandise featuring my creations and so Im wondering if anyone here would know of any good suppliers of blanks( shirts, hoodies, mugs, cups, calendars, notebooks etc etc) OR if anyone here has a P.O.D. or similar business thats looking for a graphic designer to work with. i apologize if this comes off as naive or ignorant to the way any of this works but as i said up until now this has solely been a hobby and i'm just now looking into possibly turning this into a extra revenue stream