Check out The Story Grid. It was developed by a developmental editor. There is a lot of helpful articles on the website. There is also a book you can buy and there is a podcast. My sister is writing a book right now. She has her first 20,000 words written and the story grid has been the most helpful thing for her. Also the podcast You Should Write a Book by Camille Pagán is really helpful for mindset advice and publishing questions. Camille is a published author of several books and a book coach. Also Fiction Writing Made Easy podcast by Savannah Gilbo is also helpful. Savannah’s website is also full of advice. She is a book coach and developmental editor.