the general sense that most relate "possession" with? No, they are a
spirit, not a living entity. The possessions you usually read about in
religious literature are living beings, not spirits. Often the word
"spirit" is used interchangeably with the word "entity" or
the name of the entity which results in massive confusion. The translation of
cultural texts & religious texts sometimes leads to these words being used
inappropriately which results in inaccurate assessments of situations.
If you believe yourself to be possessed you should speak with a professional. There are many circumstances where possession is mistaken for something less severe.