If you like such structures in your house, you should know what kind of hardware, tools and materials you need to make your plan come true. If you do not know what type of equipment you need for such purposes, you won’t be able to finalize it.
If you are a beginner, you should make a detailed reseasrch about building secret places in house. By doing this, you will have a comprehensive idea about such processes. For that reason, watching some diy tutorials will always be helpful if you want good results.
Full size is 562X700 (Link to full-size image) pixels.