What Am I Riddles

Question: I look green but I am not. I look blue but I am not. I look red but I am not. What am I?

Question: I live in your house yet, you do not love me. I eat your food, yet you squeal in fright at the sight of me. What am I?

Question: Act in my name, and thus remove me. What am I?

Question: I fasten to walk,
and unfasten to stop.

What am I?

Question: People are scared of me but I am loved by some. I can be your best friend but could become your enemy in a blink of an eye. What am I?