You should be able to print or save from there.
If your printer dialog box has a feature for borderless printing try that. it will help center and fill the page to the edges.
Sometimes that doesn't work so click on the image and drag it to your desktop, where it will become an icon.
* Then right click on the icon to get a menu, choose print
* Now you should get a preview with a small image and a choice to fit picture to frame. choosing the fit picture to frame should allow a full image to fill the page.
If it doesn't
* From the same preview choose options (not print) then...
* click on printer properties then
* Features then
* Next click fit the page or borderless
* Then ok
* Then print.
If it does not come the correct size then save it to a word document. You can do this by right clicking on the blog picture and choosing copy image on it.
Next open up a blank word document and past to the word document. It should come the correct size and orientation.
If it still doesn't come in the correct size then click on the image that you pasted into word- it will have some lines around it and circles in the corners. Put your courser on the corner circle and drag to enlarge the image.
If the image does not want to fill the page or if it wants to go to the right side and part of it disappearing then the preset margins are in the way. If that happens look to the toolbar at the top of your screen and click on the tab for page layouts. On the left is an icon for the margins, click on the icon and scroll to the bottom for the custom margins feature. Reset the margins to 0 and save (It will only affect this document). The image should fill up the page and print nicely.