There are lots of places where you could get your book published, but sometimes finding the right place is hard!
In many cases finding an agent is extremely important. They can help you tweak your story for publication. Agents have a bigger pool of places to submit work to, so a person with a good agent will likely do better than a person without. They also can help you get better contracts, money and answer questions you need answered. If you are thinking about an agent, submit to agents first. They get back to you faster, and won’t be able to shop your manuscript to editors you’ve already submitted to on your own.
You can find an editor before you get published. There are a lot of great publishing companies that do accept manuscripts/dummies from individuals. Do your research on these companies. Publishing companies should pay you, and you should not be paying anything out of pocket!
The Book by SCBWI — A publishing guide with kidlit places to submit your work. Must be a current member of the SCBWI to access. https://www.scbwi.org/online-resources/the-book/
The Writer’s Market Books — A series of books created for writers and illustrators to get their books published. Recently acquired by Penguin Random House so the website may change. https://www.writersdigest.com/WritersMarket