This help page describes how to cite the same source in multiple places on the same page. If you're citing different pages from that source at different places on the space page, I'd create different citations that include the page number, but you could do an abbreviated form after the first one (i.e., in the first citation of a will, you might give a full citation including county and state, volume number, pages, name of testator, the date of the will, a link, etc.; in the later citations, you could just put something like "John Smith will, page 413, [link]").
I'm not quite sure what you're wanting to do with your first example. After you've created a profile, you can link to it using [[Wiki-ID|Display Name]]. Within that space page, you might just need to put a note next to the name - something like "same person as #3 in list from Philip Alston's 1820 will". If you don't have a profile with a Wikitree ID yet, there's not any way to link to a person.
