Commonly, you’d express this as either
SELECT COUNT(*)
FROM employee
WHERE name like 'kaushik%'
AND rownum = 1
where the rownum = 1
predicate allows Oracle to stop looking as soon as it finds the first matching row or
SELECT 1
FROM dual
WHERE EXISTS( SELECT 1
FROM employee
WHERE name like 'kaushik%' )
where the EXISTS
clause allows Oracle to stop looking as soon as it finds the first matching row.
The first approach is a bit more compact but, to my eye, the second approach is a bit more clear since you really are looking to determine whether a particular row exists rather than trying to count something. But the first approach is pretty easy to understand as well.