Looking for a traditional publishing contract?
You need a literary agent.
A good agent will work hard to sell your book to a publisher and negotiate a bigger advance and better contract than you would for yourself.
Once you’re aware of character type, you’ll find yourself noticing it more and more in what you read and watch. You can then use this awareness to study that character and see what elements you can use in your own writing.
The megalomaniacal CEO. The sociopathic killer. The suicidal teen. The anxious woman self-medicating with booze and pills while caring for her demented mother. As writers, we invite these characters into our stories because they are true-to-life and because their psychological problems invite curiosity and compassion.