My daughter has the D5600. She had the 18-55 Nikon, a full frame 70-300 VR and a Sigma 105 macro. For her birthday last year, I got her a Niklon 18-200 as a lens she could use on certain types of outings without having to change lenses. She used it a few times and it has been gathering dust every since.
Given that you enjoy landscape photography, I would suggest that you get something to fill the wide angle range first. I got my daughter the Nikon 18-20 DX, and she loves it. Those can be had for a tad over $200 used. Of course, everyone has different shooting styles, like and dislikes.
It's nice not to have to change lenses. It's even nicer to bring home sharp images. It's difficult for the manufacturers to produce lenses with a high zoom ratio that perform well. Also, I wouldn't invest too much money in lenses until you are entrenched enough in photography to know whether you are likely to stick with a crop frame camera, and also if you possibly might move to mirrorless in the foreseeable future. Yes, you can adapt F mount lenses to a mirrorless camera, but I can tell you from experience that you will want the native Z mount lenses after a while. Likewise, you can use a crop frame lens on a full frame camera, but you give up using half the sensor when you do.