i am writing some custom wordpress pages, and that i want that whenever an action in which the user has addess a product to a listing (following the user press the submit button and also the page reloads showing the up-to-date list) a messagge seems on the top from the content area saying something similar to "the product xxxxxxx continues to be added." after which fades away soon after seconds (or it might stick with an "x" right to shut it).

There's any function in Wordpress that enables meto do this? The diminishing is optional, but i wish to provide the customer some type of feedback (maybe inside a eco-friendly-border on whitened box or something like that like this).

Also optional but interesting is always to also have the mistake message, the same just red-colored border rather than eco-friendly.

The content needs to show within the page, not over and it has to not be modal nor an js alert.