Angels are beings that can take different shapes in this world.
The pillar of cloud that went ahead of moses and the isrealites was an angel.
The burning bush was an angel.
Two angels waited for the womans when they came to jesus's grave.
An angel appeared before john the baptist's father.
These are just some examples I plucked from my head... there are many many more I know.
Angels are described many many times in the bible.
They have no shape in this material world, they can take any shape they(god) desires.
Michael