Kuldeep ji rightly answered your query. I wish to add the following points:
1. RC is for you, i.e., PE, and not for contractors, as you mentioned in your query.
2. Kuldeep ji has provided a list of basic documents required to obtain RC and License. In addition to those documents, each state government has its own list of additional documents. For instance, some states require affidavits or undertakings from employers for specific compliances. Each authority follows a different procedure.
To discover the necessary forms, formats, and other required documents and procedures in your state, it is recommended that you reach out to the appropriate authority.