MY printer dots per inch is 600 x 600 dots per inch and I can't change it to 300. How do I change it?
You don't, that is the DPI printer will print.
Program that you use to print tells the printer what DPI to print.
If the image is 300DPI the printer simply prints each dot 4 times.
So go to MS Paint and see what the DPI is.
Then if the DPI is 300 all is fine.
Just do the adjustments I told and insert the paper.
Then go to print setup (still in MS Paint) and specify the paper type, paper size and wanted print quality in there.
Then hit print.