If you want to make screenshots like then get the mod "Photo Mode". It hides all the menu.

If you want it to look like how I showed you last section, follow these steps. First, go into People Playground, enable "Photo Mode" in your mods. It is the only necessary mod you need, but you can enable other mods. Second, choose a map. I used default for the screenshot shown, but it does not matter. Third, posing. Get a human, pose him the way you want and put your game into pause (not the menu). Then, press P (to hide the menu) and take the screenshot.

When done, you can publish the screenshots to your profile.