It's a great device but be aware of the differences between the Exynos and Snapdragon versions. I had the Exynos and the battery was terrible and it kept dropping calls. I have ordered a Snapdragon version from Hong Kong which I'm sure will be much much better.
There is a huge diffeence between the performance and battery life of both versions. You never said which country you were in and neither did the person who has replied already.
I would avoid the Exynos at all costs but the device itself is magnificent.
Yes, it has a SD card slot. Some variants are dual sim and allow either 2 sim or 1 sim and 1 SD card.
UK is Exynos. Have a look on Youtube for comparisons between both versions, but the performance and batery life of the Exynos isn't great. I guess if you're not a heavy user it doesn't matter so much but I found it significantly worse than the Note 10 plus, and most UK reviews do mention the battery life as inadequate.