I've started a local business. (Need guidance)

It's been a couple of months now that I'm selling Mugs in different designs:

I always wanted to start my own business. In the past 2 years, I've been trying to come up with an idea for a startup. I read many books about business and finance. I've spent many hours analyzing all the ways that I can make money, based on my current socio-economic situation. I also considered personal interest. In the end, I came up with the idea of selling mugs.

I started buying them one by one from an online product supplier. Because I had a low budget, I carefully selected a number of mugs with the most beautiful design.
After receiving them, I try to take some photos of them, and sell them in my retail store:

I managed to sell a number of them, especially after advertising them online.

I have many ideas about this business, and I want to improve it one step at a time. For now, the next step is to purchase the basic equipment for creating mugs with my special design.

This is the beginning of my business. I need to learn a lot of lessons and use the knowledge and experience of others. I'm looking for any advice, idea, or lessons that anyone can share. I'm also willing to have a conversation with other individuals who are running a business or trying to start one. I appreciate your support, thank you.