First Left Click on that "LINK" it will take you to the link's web site, once there find the programs' download "LINK" and again with your "MOUSE" left click on it, a download dialog box will show up and click on save, make sure that you save it to your computer's "DESKTOP".
The program is a "ZIP" file so you will need to use an "UNZIP" utility program to "UNZIP it" a program such as WINZIP or 7ZIP or some other such, use GOOGLE the search engine to find with such a program a FREEWARE unzip program.
First go to the address space up on the browser and type
www.google.com
And then press the ENTER key on your keyboard once you see the GOOGLE BOX enter on it this:
freeware unzip program
Then press the enter key, it will show you site's links click on one of them and find and download an unzip program, then once downloaded find it and left click on it twice very fast, let it install on your computer, let it "Associate" itself with your ZIP FILE then left click 2 times very fast on the SODUKO zip file and unzip it somewhere try to make it unzip on:
C:\Sudoku
Once there find it and if there is an EXE file there, that is a file with an .EXE in the end of it click on it and just go from there.
I really can't help no more on this, find LOCAL help, a friend or relative or go to a public library and ask for help from somebody there and or find a computer book there.
If you can't find help, let me know and ask me questions about what you need and or want to know.
Good luck.