Castle tour through England and Scotland

Hi there! My fiancé [25M] and I [23F] are getting married in a month and are wanting to do our honeymoon for our one year anniversary next year. Something we always talked about was going overseas and doing a castle tour through England and Scotland. Neither of us have really been out of the country other than Canada and no matter how much research I feel like I’m doing, I’m so lost on how to plan this and where to begin. Has anyone ever been or live in the area? Is there any advice anyone can give me or tips on planning? I feel so lost. Thank you!