Try:
data have;
length name $ 40;
input name;
datalines;
NaveenKumar
HarishChandra
SivaKumar
;
run;
data want;
set have;
length firstname lastname $ 30;
retain rx;
drop rx;
if _n_ = 1 then do;
rx = prxparse('/([A-Z][a-z]+)([A-Z][a-z]+)/');
end;
if prxmatch(rx, name) then do;
firstname = prxposn(rx, 1, name);
lastname = prxposn(rx, 2, name);
end;
else do;
put 'ERROR: Unable to extract firstname/lastname from data';
put _all_;
end;
run;