See this note that describes how values are determined for models involving interactions. Pay particular attention to the Introduction which tells you to avoid using the ESTIMATE and CONTRAST statements when the equivalent can much more easily be done with statements like LSMEANS, SLICE or LSMESTIMATE can be used. Many examples are provided in this note and in other notes that you can find at support.sas.com.
ANOVA, or Analysis Of Variance, is used to compare the averages or means of two or more populations to better understand how they differ. Watch this tutorial for more.