Manaing Banner Ads across mutiple posts.

As I make my journey through WordPress, at times I come up with a question that to many will be silly, but I cant seem to find the right “solution”.
I am looking for a plugin that will allow me to update and add Affiliate banner ads across multiple posts.
In essence, one place where I can control them.
I have older blogs that I would like to refresh the ads in them without having to go into each one and manually do so.
Any advice to what works well for someone that is not a developer, but does know the basics of wordpress.
Thanks for any help.