I am 35 years old. My spirometry answer is: further examination for extrathoracic flow obstruction & expiratory tracheal stenosis. Help me. Is it cancer?

Can't tell. Possible but there are other obstructive etiologies. Likely will need bronchoscope to look inside trachea . A ct scan provides guidance to level and degree of obstruction.
No. Unusual to have lung cancer at 35 ! this suggests something like a blockage high up in your trachea. Are you a smoker? Consult with your pulmonologist.