Is a post hoc needed?

I have completed an ANOVA test but am unsure what it all means, including whether or not a post hoc is needed and what exactly the 95% confidence interval is stating. So what exactly is a 95% confidence interval stating when, for example, the lower bound is 2.24 and upper bound is 2.77?

Then, how do I know if a post hoc is needed from my ANOVA results?
Thanks!