pressure = force / area, use that or area x pressure = force (since force is usually the one measured in n or kn thats probably what youre looking for, if im wrong just use the first formula)
unless your sieve is even smaller than 100 mesh (highly doubt) i dont think thats necessary given how fine it already is
You can look it up online. There's calculator on sites that carry ingredients for pill pressing. Or they'll have something close. Also check youtube search pill press calculations. Udemy also has formulations n much more. Hope that helps