Yes they can
Yes, multi-celled organisms and even single-cell organisms can move on their own.
yes.
Single-celled organisms.
yes
yes
yes
If a single cell is living on its own it is called a single-celled organism. There are millions of single-celled organisms alive today.
No they are not simple creatures because they have to do everything themselves such as: make their own food and storing their own food, ect.
Single celled organisms are examples of living cells that are organisms. Most other living cells are parts of living organisms, but could not survive long on their own.
An individual living thing that carries out all its own life activities is an organism. This ranges from single-celled organisms like bacteria to multi-celled organisms that barely do anything like plants all the way to the most active organisms like humans and dogs.
No
They are called autotrophs.