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These 18 dots are the whole study: one set of reaction times, and no way to run it again. Draw a resample (18 of these same measurements, taken with replacement) and watch which dots it picks.
Resample your own measurements with replacement, watch the means pile up, and read the middle 95% of them as a confidence interval.
Most statistics courses hand you the standard error formula before you know what it estimates. The idea underneath is simple: rerun the study and you would get a different answer, and the spread of those answers is what an interval describes. You can't rerun it, but you can resample what you have, and the block below does exactly that.
You describe the goal in your own words and the plan asks questions back until it is one you would follow. Goals usually look like these.
There is no fixed syllabus. The plan is built around your goal and drops what it does not need. These are the topics it draws from.
Each one has its own lesson block to try.
See how it works and what it costs.