How to add page borders in invoice

how to add page borders in invoice

That would require a custom theme.

can i have the html code for A4 size

You don’t need any html code to add borders, just use the options provided in your browser’s print dialogue.

The page borders are not visible in the broswer print also

I have edited your post to remove the PDF attachment, which could pose a security threat to other users.

Also, I’m not sure I completely understood what you meant by borders and I can’t see how the PDF attached relates to your original post.

Please explain in more detail.

you can clearly see in the pdf ,that it doen’t have page borders, ihave tested the code with page borders in online html viewer.
it shows the page border,but i have used the same code in manager theme, it doesn’t show up.

need solution for it

What html code? Could we have screenshots of that.

Manager themes are not written in HTML. They are written in Liquid.