What do I have to change from 32 bits to 64?

[dedndave]

in the upper-right corner of the forum, there are a few links
poke around in there - there are several good sources for documentation
you will also find the masm32 sdk package download
download and install that - it is a good place to start
you will find tutorials, examples, help files, and pre-written libraries and macros for 32-bit code
if you want to learn 64-bit, you really need to learn 32-bit first

[xassiz]

Problem solved, I finally installed MASM32, you can close the post.