What is the best Sigma lens I can buy for my Nikon Z8 to take landscape photos of mountains? I am honestly so stressed out right now because I just spent a ton of money on this Z8 camera body and I just realized I have no clue what lens to actually put on it for my trip to Glacier National Park in August. I saved up for a whole year for this vacation and I really dont want to ruin the photos because I bought the wrong thing.

I keep seeing people talk about Sigma lenses being a better deal than the official Nikon ones but when I look them up online there are all these weird codes like DG DN and Sport and Art and I am just totally lost. Do they even fit on the Z8 without some kind of extra adapter? I heard something about a FTZ thing but I dont know if that makes the quality worse or if its hard to use for a newbie.

I have about $850 tops left in my savings to spend on this and I just want something that will make the big mountain views look clear and sharp. Is there a specific one that is good for someone who doesnt know how to do fancy settings yet? I just want to make sure I dont buy something that is meant for like bugs or birds instead of big scenery. Sorry if this is a really dumb question I am just super overwhelmed by all the numbers...