How to delete obsolete or rarely used email addresses

Hello, I am not talking about recipient addresses but the ones that appear on an online application form which happen to be mine. Currently, i have 4 in Mac mail ( Google, iCloud, Hotmail and Yahoo) but only use one regularly, ie Google, the others very occasionally if at all. Two others also appear which are completely obsolete as they are associated with broadband providers I no longer use. In any case, I only want one to appear in the box requiring and email address, and that is Google. Is there any way I can delete the others ? Thanks