Yes! Completing a book is an extraordinary achievement. You’ve devoted a huge amount of time and effort to getting this far. It would be a shame to launch your book without polishing it first.
Even Hilary Mantel, JK Rowling and Bill Bryson have editors — several of them, in fact, brought in to critique and refine the manuscript at different stages of the publishing process.
No one is going to stop you from self-publishing an unedited manuscript, but reviewers can be quick to condemn lacklustre storytelling or sloppy punctuation.
Working with a professional editor will allow you to publish with confidence.