I want to add after: elements into inline css. I know about internal but I can't perform same for inline.I want to add after: elements into inline css. I know about internal but I can't perform same for inline.

I am uncertain, however, I believe that psuedoelements can only be used in stylesheets and within the head under the <style> tag. It seems that it would be kind of pointless to add an after/before element to individual <p> tags, when you could just write it in, in HTML.

There are other options, like

<style>
#p01::after {
content: url(something.png);
}
</style>
.
.
.
<p id="p01">
CONTENT
</p>