I wonder how everyone there gets phone cards ?

Taobao has it for sale. One card can be used in multiple European countries. Buy it in advance, and you can use it directly after landing and inserting the card.

Buy online, universal in European countries

I'm using a card launched by ifree and visa, with 300 MB of traffic per day and global roaming. It's very convenient, and you can purchase it through the apps of major banks. I bought it through the Agbank app. But you might be too late to buy the ifree card this time. You can buy it later and recharge it every time you go abroad, which is very convenient.

Many European cards on Taobao have Iceland.

Taobao