https://www.vpnmentor.com/reviews/avg-secure/
If you want to experiment, use (eg) the free VPN built into the Opera browser knowing that is for testing purposes, not a reliably secure VPN, but remember that for anything that is "free", you are the product, and your data is being sold on to pay the providers costs and recover a handsome profit. A bit like Google Search, Android, Gmail, Google Chrome, Facebook etc. This rule applies to VPNs as much as it does social media and anything associated with Google.
Should you want to use a VPN on a regular or permanent basis, then you need to pay for it. Some offer free trials, other offer 30 day contracts, so no major financial risk attached. There's some good reviews and comparisons on the VPNmentor web site linked, but also cross reference with other articles on VPN trustworthiness.
