First off, it depends what type of Visa gift card you received.
If you got a Metabank or Pathward Visa (it will say on the back of the packaging "This card is issued by Metabank or Pathward...), those are the best ones as they pretty much can be used anywhere without a problem as long as you register them first.
If you got a Vanilla Visa or a Virtual Visa or one from some other bank, those are the ones as you said that are tricky to use as they don't seem to work at a lot of merchants. Usually those will work at
Amazon or they should work in a physical store. (There are probably other online retailers they will work at, but if you try one that it doesn't work at, it can end up freezing the card.)