It is a lot of fun. When people say 'focus stacking', they often mean the whole process of taking pictures at different focal points, and then merging them into one picture with deep focus.
But actually focus
bracketing is taking pictures at different point of focus, where most of the subject is out of focus in any one picture. This is done with the aperture fairly wide (f/6 or so), for maximum sharpness of what is in focus, but most won't be in focus for any given picture.
Focus
stacking is where the focus bracketed pictures are merged --> one picture with deep focus.
But the term focus stacking is commonly used as a short-hand for the whole process.
I don't know the features of the R10, but here is one with the R7:
https://www.youtube.com/watch?v=bJOtUBSCWbQ&t=410s To be clear,
The R7 can do both --it can do the focus bracketing and then stack the pictures for you, in-camera. I don't know what the R10 does. But if it only does bracketing, then you would do the stacking with separate software such as Photoshop, or with dedicated stacking software like Zerene Stacker.
Various issues may arise, like whether you are bracketing the pictures to focus thru the subject, focusing farther and farther away from you, or if you were bracketing to focus toward you. If the latter, then I can see why one picture would be in focus, and the rest are out of focus -- they were trying to focus on the foreground. The direction that the focus changes is in the settings.
There is also focus stacking in landscapes, but that is very different. That is for a wider angle situation, with a foreground subject (say, flowers), and mountains in the background. There are YouTube videos on the subject.