Hello; I would like to know the different grammar rules of complex noun phrases; for example the correct verb tense, when to use it and how is this form ( the gerund goes first or the subordinate clause etc)
I'm not exactly sure what your question is. Gerund phrases can be noun phrases, but is that what you are wondering?
Here is a page on gerund phrases:
Gerunds & Gerund Phrases
I'm not sure if that will help or not.
Do you have an example sentence that you have in mind?