No matter which route you take, seeking out a traditional publisher or choosing to self publish, there is a lot to do. Consider your options, weigh the cost, do your research. Don’t get taken in by a deal that sounds too good to be true, it usually is.
If you are asked to contribute financially to your upcoming book, for editing, for printing, for cover design, that’s all part of self publishing.
There are sites available to warn you of publishers with less than honorable intentions. I would highly recommend you take the time to look for them.