You have to create your IG account from your mobile 3G/4G IP.If your carrier is blocking IG then you have a problem and have to buy a mobile proxy.
With a quick search you’ll find plenty of topics about instagram proxies like this one
There are a few providers but from all the threads i saw everybody is happy with @HenryCooper proxies.
Regarding the vpn it might be a good solution for browsing and avoiding internet blocks but i don’t recommend using it for IG account creation.
The former Chief Security Officer (CSO) at Facebook explained that a normal number of visited websites in the last 10 days is one of the biggest factors Facebook uses to differentiate between the real and fake users on Facebook: