A poser is someone who’s influenced to act a certain way in order to impress others. These people aren't genuine or being themselves, they say. Alternatively, you can say "I feel like a fake."

A poser is a person who dress or behave with the sole intention to impress others. The person may or may not be a fake pretending to be someone the person is not , but a poser primary aim is to be a show-off out to impress others , and his actions are all done for attention. "i feel like a poser"> this can probably mean that you are overdressed for an occasion , and you think people might be thinking you are showing off