You could try using something like https://receive-smss.com/ to receive the SMS for you. I suspect a lot of these numbers will be blocked by Google however.
Also keep in mind you might well have problems in the future though if Google want to send you an SMS for 2 factor authentication, its possible someone else could also recover the password to the Google account you create if using a number on that site.
As i know its only possible without phonenumber on Computers (saved in Browser Cache) where already a google account exists and is active in use. To prevent from creating fake acounts. So u can try on a Computer where already one exists. Google has some unknown rules for suspicious activity like anonym IP or atypical locations.
A few month ago, I tried to register a new email, but I was asked to enter my phone number again to continue registering. I don't think this is possible When there was no way, I used a virtual number.I used a virtual number instead of my original SIM and verified my account