When using critical value approach for decision making with a hypothesis test, proceed as follows:


left tailed test (if test statistic < critical value, then reject Ho), if not, then do not reject Ho
right tailed test (if test statistic >= critical value, then reject Ho), if not, then do not reject Ho
two-tailed test, (if test statistic falls in between the critical values, do not reject Ho, if not then reject Ho


for p-value if p-value is > = alpha level of the test, then reject Ho, if not then do not reject Ho