See update at the end of this answer. I edited your question to state the most important bit of info, based on your adding tag
terminal-emacs to it: You're using Emacs in terminal mode.
You can likely ignore those warnings.
However, you should not see those warnings on MS Windows, I believe.
What happens if you do
C-h f x-display-pixel-width? On MS Windows, Emacs 27.2 (the latest release), started with
emacs -Q, I see the function described fine.
Your question is incomplete. What Emacs version are you using?
Where/when do you see those warnings? I assume it's when you byte-compile some file (those are byte-compiler warnings), but please specify (provide a recipe to reproduce).
Do you see those warnings if you start Emacs on MS Windows using
emacs -Q (no init file)? If not, bisect your init file to find the culprit.
Oops. I see now, from a tag you used, that you're using Emacs in terminal mode. There is no support for pixel-granular functions in terminal mode. That's your answer. The library you byte-compiled likely won't be able to support some pixel-relevant behavior. (It may be able to do other things, however.)
See the Emacs manual, node Glossary, entry Text Terminal:
A text terminal, or character terminal, is a display that is limited to displaying text in character units. Such a terminal cannot control individual pixels it displays. Emacs supports a subset of display features on text terminals.