where do i locate the pop folder

hello

I am trying to locate an email from the end of November and emails in account only go from beginning of December.   I have no idea about this pop folder I cannot see this anywhere their is nothing under deleted folder just showing empty the settings are set not to delete etc..... also most of my emails go into junk folder and the one I'm after is my wageslip which always go into junk.  I am using Microsoft edge.  I'm not very up with technology in layman terms if anyone could explain how I can access them please

thanks