The best way is to make profiles for the ancestors you know, add all the details and sources you have.
Once you have a profile for John Nesbitt you can use the dropdown menu for the profile name and select research.
Follow the instructions and you will get to a screen with his name and details. At the bottom there are links to several online resources. When you click one you will arrive at the site with all the information already input to do a search.
Good Luck and Happy New year.