There's a few things that need mentioning that I thought I would say based on what I saw in the video.
In combat you were often standing still while just trying to aim. Obviously you probably should dodge while attacking, but this isn't really easy when you have attacks on far keys like 6 and 7. You would have an easier time if your spells were on keys a bit closer to WASD, or on mouse buttons. You also don't have to use all the spells you own; fire touch isn't going to do you much good in a fight, so it's okay to put on a far key, at least until you have another spell that you like better for breaking background objects.
You left the cave on foot, but as the tutorial said, you can just use the warp gates to warp out when you're done exploring. Also, you don't ever have to manually exit the warp gate if you change your mind. Just select the gate you just entered as the destination.
The minimap in the top left shows loot, doors, and bosses. Each color means something different but you generally want the green and orange things. This helps you quickly collect the goodies in a room. In addition, visiting every room in a dungeon really is usually a waste of time; in the tutorial there's some extra items in those caves but it's generally just granite, quartz and enemies, which you can find everywhere underground anyway. This isn't always the case, as maybe you really do need granite, or there's something else useful in the region, like coral. Either way take your time exploring, but just remember that these two tools are very useful for quickly acquiring what you need.
And finally, don't forget you have storm dash when you need to get around. If you wish, you can doubletap left/right to activate it even if it's not on a hotkey. Alternatively, if you don't want it to go off accidentally (and believe me, there's MANY ways it can kill you), then you can disable the input in the options and put it on a hotkey instead.