I've so many links in different website for a particular page in sitecore. I want to allow Editors to configure the redirection for that particular Item to a new page.
What is the best way of doing this?
You can use redirect module : https://marketplace.sitecore.net/Modules/301_Redirect_module.aspx?sc_lang=en
Github repository where you can get the code and to modify it: https://github.com/Chris-Castle/301RedirectModule
On the redirect module you have the option to create rules for redirecting your requests to other landing pages.
If you need to do some custom logic during the redirect process you can consider creating a controller rendering with a template that contains the link to redirect too. Then content editors can create items based on the redirect template.
If you need redirection on an existing page you could create a base template containing the redirection link and inherit the base template on the applicable page templates. Content editors might need to manually attach the controller rendering to presentation details in this case.