I do the same type of photography - typically I'll have numerous frames for the sky, single very long exposure for the foreground with low ISO all taken without moving the camera or changing composition, and then blend them together -
if that's all you're curious about then you probably don't need to read the rest - a lot of detail to follow if you're curious.
All the sky frames need to be properly aligned because of the planetary rotation, so I'll typically choose the first/middle/last sky exposure to align to as not not feel like I'm cheating in putting the milky way somewhere it wasn't or changing composition (personal guideline - otherwise I feel like it's not that different than a sky swap from another location or night, which I'm not into). Occasionally I'll put a lit tent into the frame, and in those cases I'll also need to add some exposures to manage the brightness of the tent, and light leak from the tent on to the foreground. I've included a couple examples below with what I did to get it done as examples. Admittedly, these are not for everyone's taste, but I do like them.
View attachment 186679
5D IV, Rokinon 14mm f/2.8.
Sky - 8 frames, ISO 8000, 20 seconds. All frames manually aligned using warp (that distortion is nasty - this takes forever), then converted to a smart object and set to median blend in PS.
Landscape - 2 minutes (speaking from memory here) at around ISO 2000, brought back to darker luminance in photoshop
Tent - two frames with a light on - one to illuminate the ground around the tent appropriately, one to not blow out the luminance in the tent (I can't remember the settings of each for the life of me)
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This one didn't work as well because of the tree overlap with the sky, and a lot of haze in the sky requiring me to push ISO higher than usual. If you look closely near branches, you can see spots which couldn't median stack (because when you align the stars, the tree will appear to be moving) and had to be included with only noise reduction from a single exposure. I've included this example because I think comparing those less than ideal spots near the branches against the open sky gives you an idea of how much noise reduction and increases in detail you can get from an 8 image median stack relative to a single frame in one instance.
5DIV, Rokinon 14/2.8.
Sky - 8 frames, 20 seconds, ISO 10000 (honestly, increasing to 16 frames would have been a good idea here)
Foreground rocks - 1 frame, 2 minutes ISO 2000 (speaking from memory).