Native 300 DPI Images VS Modified Images Using Phoyoshop

Long story short : divide the width by 300 and you will get the real printable size (in inches).

I.E : 1920 px/300 : 6.4 inches wide.

Also check the preferences > Tech something and check the first box

Then when you will resample an image select this option in the dropdown menu.

Also Camera Raw has an option to enlarge; you can find it on the tree dots side menu. It will raise the resolution with less quality loss.

Hope it will help 

"The seller from Etsy gave me image size requirements and resoltion requirements.  Resoltion is 300 DPI minimum."

Wrong way to communicate with customer. You already have good explanations, your seller is communicating in wrong way with you. He should mention dimensions not resolution in PPI or DPI. Nothing wrong with you in my opinion, its seller mistake in communication.

A PPI/DPI resolution given without an actual print size is worthless. What is the exact SIZE (dimensions) that are required?

And you can't just download a low resolution image from the web, increase the PPI/DPI and expect it to work: what counts is the actual pixel resolution, or details/information in an image. If you blow up a 500x500 pixel image to 5000x5000px in Photoshop the pixels will merely be blown up to blurry mess. If there are no details in an image how can you expect those details to be recreated/generated? Magic? Obviously that will not work.

The first thing to do is to change Google's image search parameters to find high resolution images only. Better, use Bing or Duckduckgo instead, because Google's image search doesn't display the image resolution anymore nowadays.

Change the search options to find high resolution (large/very large) images only.

Now notice that a few of the images are over 3000px wide and high - those could be used for a comfortor - probably.

Look at that: an image size of 4774 by 4561 px! That is quite decent. Download the high resolution image. At 300ppi/dpi it can be printed on paper at a max size of 40.42 by 38.616 centimeters. For a comforter this should be okay, because print resolution on a comforter's textile is much lower than on paper.

But for a bed sheet cover/comforter ideally you'd need around 7000 by 8000px, or similar. And PPI is completely unimportant here, because it means "pixels per inch" - 300ppi at the size of a comforter is WAY too high resolution.

In short: try to find an image of the band Rush at a minimum resolution of around 5000x5000px.

Any image below 2000-3000px is probably not going to cut it.

But to be absolutely certain about what the designer needs: ask for a minimum and maximum PIXEL resolution for width and height both. That will tell you what resolution you must deliver. PPI/DPI is a useless value in this case.