Heading styles (further questions)

Hi Richard. Thank your for your response to my query. It has partly helped but I need to set a style(s) as follows:

1.00 MAIN HEADING IN BOLD

1.01 Sub paragraph text

1.02 Sub paragraph text

1.03 Sub paragraph text

1.04 Sub paragraph text

2.00 MAIN HEADING IN BOLD

2.01 Sub paragraph text

2.02 Sub text here

3.00 MAIN HEADING IN BOLD

Hopefully, you should get the picture (tried to make it as clear as possible). The sub paragraph numbers need not be indented. Any advice would be gratefully received! Paula