Couple of weeks ago I got my galaxy M30. Now I applied a Bumblee skin from gadgetshieldz. Take a look at my M30 now.
Here is the link from where i've purchased:https://www.gadgetshieldz.com/galaxy-m30-skins-covers-wraps.html
Since it's a curved screen I'd recommend you to go for flexible tpu screen protection film that is scratch resistant . I'm using a screen protection film from gadgetshieldz and it's way more convenient than going for a tempered glass or UV glass with...
Don't know about the first two. But yes, you do need a screen protector along with the case. I'm using a flexible tpu screen and body protection film for my tab. It gives scratch resistance and the spen glides on it, so smooth and good touch response...
I suggest X Glass from Gadgetshieldz which is not expensive and the quality is great. It is good with a fingerprint sensor because it is smudge-free so the fingerprint will properly scan and also it covers edge to edge! I'll share a link below for yo...