Yes, CAGR is a use case of geometric mean. As such, it is the geometric progression ratio that provides a constant rate of return over the time period.
I wouldn't say they are the "same". I mean they are distinct concepts, but yes, the geometric mean can be used to calculate the compounded annual growth rate.
The following uses R to calculate the CAGR, using Example 1 at the following link as an example. Note that using log is a little simpler than their method.
Note one distinction is that the rates need to be adjusted so that 1.00 indicates a return of 0%, so 1 is added to the returns. In turn, 1 is subtracted at the end of the calculation.
Geometric mean and compounded annual growth rate are not same but are two different concepts.
Geometric mean is a measure of average in general while compounded annual growth rate is rate of growth. Compounded annual growth rate i(or equivalently coefficient of growth) is a coefficient in the mathematical / statistical model describing growth of the associated variable.
Of course Geometric Mean can be used to compute compounded annual growth rate in some situations.