This is not a Tagalog word.
H9w is a typo.
On a full keyboard, you can see that the number 9 is above the letter “o.”
It can be surmised that people who were intending to type out h-o-w, ended up typing h-9-w by mistake.
Example of this common mistake:
❌ So h9w are you?
✅ So how are you?
