Looking help with landing page

[BHP]

HI,

I have been trying to setup a landing page in cloudflare, I am able to setup back button script in it, though I am not able to make push code work on it, trying to add push subscription code, propush says add .js file in root folder, I did add it in cloudflare, landing page I made is in cloudflare app "quick" even though the .js file show in url when I try to access it, but push subscription does not show in landing page.

Is that even doable in cloudflare, or should I host landing page in hosting