I hate to be blunt, but I don't think you wasted your money on the SD card. That can be used on any phone and will work well for storing media and other independent files. If the ability of playing PUBG was part of your decision to buy the phone itself, then I'd say you wasted $30 on a phone that has no chance of playing it at all. The specs are abysmal for gaming, even if storage wasn't an issue.
But I'm guessing you already had the phone before you considered paying PUBG. It's not uncommon to get a cheap, "entry level" phone as your first Android, not realizing their limitations. I've been there myself. These phones have their place, but doing any sort of gaming is not it. If you can give us an idea of your budget and any other considerations you have, we can suggest a phone that would better suit your needs.
If you are set on wanting to play PUBG on your current phone, I don't think there's anything we'd be able to offer that helps. I'd be surprised if the game even shows in the Play store for it (which means it's not compatible at all).