How do proxies work?

I was wondering how proxies work for instagram on creating numerous accounts. do you do it on computer/laptop or iPhone/iPod ? also, how would you activate proxies or whatever? is it basically like changing your IP address? do you still need to phone verify your accounts when created under different proxies?

You buy proxies(ip address) from provider. To authenticate the proxy for use, you either input username/password or you input your isp ip. You can use it for any device that support proxy. Where ever you can use proxy and log in to IG, you can create accs from it. Proxy are ip address you use other than your home ip. Yes, you are tricking other software or website thinking you are from another country. You still need to phone verify IG acc regardless of any ip you use.

This sounds all too easy and it is not. You will learn that it is much harder to create mass IG accs.