There are several reasons why you might decide to use a VPN:

The first reason you might use a VPN is to access content exclusive to a particular geographic location. If you buy Nexflix in the USA you can see the content Nexflix has negotiated to share. In other countries they may have different agreements, and you may like the agreements in Mexico far better than those of the USA. With a VPN you can appear as though you are in Mexico, and thus access this content.

The second reason is that you are concerned about targeted ads, intelligent airfare pricing, and other IP based tracking. This is another viable reason to use a VPN, especially if you are regularly running into issues of IP blacklisting, etc.

The last, and most cynical by far, is that a techie friend admonished you for your lack of security concern citing the dire risks of privacy invasion, identity theft, data mining, and spyware. After all, your ISP can see what you’re doing without a VPN, and they must be using this data, right!? These not being your concerns, and perhaps are not even being legible as presented, you heed the warning at a cursory level, buy a subscription to the first VPN service you come across, and download the software… now if you could only remember how to turn it on…

If you fall into one of the first two categories, this link may be helpful…
https://www.pcmag.com/picks/the-best-vpn-services