I filed the form i539 to change my status to f1 and it''s still pending. if i apply green card right now would it affect my case of f1 decision?

As you filed the change of status to F-1 prior to the application for the green card, the green card application will probably not affect the adjudication of the change of status request. If the green card application is denied but the F-1 change of status was approved, you would likely be allowed to stay in the U.S. as long as you are maintaining student status. You should remember, however, that F-1 status is tied to non-immigrant intent. If you require another adjudication from U.S.C.I.S. or an American consulate/embassy on your non-immigrant status, the green card application would be taken into account in deciding whether to grant the application. I note that there are certain non-immigrant visas which are dual intent (H-1B, L-1) in which intent to immigrate is not relevant to adjudication. For these, individuals can hold both immigrant and non-immigrant intent. There are also others in the gray area (E,O) for which U.S.C.I.S. and the consulates would likely approve an application notwithstanding immigrant intent by the applicant.