New player trying to get my first deck

I'm a new Yugioh player, I enjoyed duel masters and wanted to get the deck I use in the game IRL and also look up to start a collection. Its a deck centered around galaxy eyes dragons but I'm not sure which packs I should get. I've seen people suggesting buying the individual cards but I cant seem to be able to find a site that sells individual cards in my country.

Is there a place where I can look up which packs contains which cards so I can choose the pack that contains most of the cards I need? And if you can help me with a site that sells individual cards that ships worldwide.

I'm also open to suggestions on which structure deck I should get.

Thanks.