How can I see my devices on Apple website?

You can use the steps in the paragraph Use the web to see where you're signed in in the document linked above - Check your Apple ID device list to see where you're signed in - Apple Support

Or you could sign into icloud.com and click on the Find iPhone tab. This will provide the same list of the devices signed into your account.

Use the Find iPhone tab in that display. This will show a list of your devices.

You can also see the same list on your iPhone if you navigate: Tap Settings > [your name].