My title bar is centered and has always been that way, however, the menu bar and Ribbon will always open on the left side of the document window (if that's what the OP is referring to). Maybe I'm not understanding what he's trying to accomplish?
As for changing normal.dotm, he should be able to position the document on his screen to wherever he wishes and then save normal.dotm. New documents should then follow suit. Again, if that's what he's referring to?
OK, but you don't need to separately save the normal.dotm - or you shouldn't ever need to. Word saves changes to default document layout automatically, whenever you quit Word.
Of course, the OP is not asking about layout or document changes, just the physical position of the document window.
Show us a screen shot, after launching Word, then opening a default blank document window.
The window name is centered, of course - but the window itself is not - it's on the left screen edge.
remember, we're talking about the document window, and not the blank document IN the window.
And, moving the window (to the far right, for example), then quitting, does not change the screen position of the New document window. It still comes up on the top left edge.
Show us a screen shot of your screen (not just the Word document window) when you can change the position of that window, then Quit Word, reopen, and the Word default document window keeps that change.
I don't usually dare folks here, but no screenshot - it didn't happen.