Problem description:
I want the user to be able to type in (in the serial monitor) for example 0, 1, 2, 3, 4, 5, 6 and hit enter.
I then want Arduino to create an array of the number of elements entered into the serial monitor. I then want to be able to print that array as such, "array = [ 0, 1, 2, 3, 4, 5, 6 ]
Have a look at the examples in Serial Input Basics - simple reliable ways to receive data. There is also a parse example to illustrate how to extract numbers from the received text.