Required software development,Website Development freelancer for matrimonial website job

Hi I need to add sign up option into the current website.

Need to add sign up option where people can interact with each and search to find a match.
I want to convert the site to a matrimonial platform like www.shaadi.com. I know shaadi.com is a very big site I don't this big.

If I buy a template from www.wpdating.com then can you install the features to my current website?

Please suggest what is suitable as I don't want to change anything in my current site. So do I need to buy a separate domain and link it to my current website page or I go for subdomain.

Your thoughts and advise is highly appreciated to start the project.

Waiting for your response.

Thanks

Skills & Expertise Required

software development Website Development