Can someone tell me what function to use to return the chi-square value? I want something that will take an array of values and return the chi-square.

Could you please clarify whether you are looking for a procedure or to do it within a data step through a function?

I am pretty sure you can use the proc freq procedure as follows:

PROC FREQ;
TABLES *** * YearsEducation/chisq;
run;

What I need is a function that will return the double sum of (Oij - eij)^2/eij where Oij is the observed frequency and eij is the expected frequency. Also we get our values from a probrobility table.

If that is the case then you need to use PROC FREQ:

proc freq data=dataset noprint;
tables var1*var2 / outexpected out=output_dataset;
run;

Option "outexpected" outputs the expected frequency in the dataset specified in option "out=".
To automate the calculations you could use a macro which takes the name of the dataset and the variables you want to cross-tabulate. Then you will have to use a DATA STEP to complete your calculations.

How do I store the value into a variable x?

I guess what I really need to know is how to write a macro that will return a variable.