I need to clone a website and I need help

I would like to get a similiar site of www.manufacturers-representatives.com
I want to obviously be able to change and update info on this site but I really have no idea how this would work can someone help me? I will need a back end database to see all the information of our clients.

Cloning a website is unethical, and can lead to serious liabilities depending on its context and usage. The exception is mirrored sites, which are owned or licensed by the code holders anyway. It sounds like you want to be able to edit the original site, so no.

This should be posted in the paid forums though, since you're looking for work to be done for you.