A single phone verification unlocks the whole Google ecosystem — Gmail, YouTube, Drive, Play. Google doesn't always ask for a phone at signup, but it reliably does when the registration looks «non-typical»: a VPN or datacenter IP, a fresh device, or several accounts created in a row. A virtual number from Get-SMS receives the G-code SMS and keeps your personal number from being linked to yet another Google identity.
Google is one of the strictest services about phone reuse: each number can verify only a couple of accounts before it responds with «This phone number cannot be used for verification». That message means the pool is exhausted for Google specifically — the number is still fine for other services. Simply cancel it (no charge without SMS) and take a number from another country.
Don't add the virtual number as a «recovery phone» — set a recovery email instead, since the one-time number won't receive codes later. Sign in on the same device/IP for the first days; sudden geography jumps are the main cause of «verify it's you» loops. US, UK and Indonesian pools traditionally have the highest first-try acceptance for Google. If you need many accounts, spread registrations over time and countries rather than burning one pool.
A properly created account works everywhere Google does: the same login opens YouTube (including channel creation and monetisation onboarding), Google Play for app publishing, and Workspace trials. None of these later steps re-check the original verification number — they rely on the recovery email and your usual sign-in patterns instead.