Question on ANOVA and Correlation/Association
About what ANOVA is used for: it can answer whether the difference between the mean values for the data samples I have is due to randomness or is it statistcally significant. Then it is a significance-test that gives you an idea about whether your mean values are (statistically significantly) the same or not. A drawback is that it does not tell you which data sample/s differ from the rest or by how much (useful source).
You can think of the process as follows (as described in Practical Statistics for data scientists):


Combine all the data together in a single box
Shuffle and draw out n resamples of m values each (where n is the number of data samples and m the number of data points in each sample)
Record the mean of each of the n groups
Record the variance among the n group means
Repeat steps 2–4 many times (say 1,000)
What proportion of the time did the resampled variance exceed the observed variance? This is the pvalue.


On the other hand, the direct measure of correlation gives you a number, it tells you by how much two data samples vary linearly along with each other