The kit lens should help you figure out what you are interested in and guide future purchases. They usually come in 24-105 full-frame equivalent focal lengths. Besides that, a the 50mm-equivalent f1.8 is never a bad purchase and is very useful for street photography or portraits on the cheap.
What if they never move on to full frame? You get lower image quality on a crop body if you use full frame lenses that what you'd get with a high-quality crop lens. Also, crop bodies will keep improving and it's generally cheaper. Not everyone can afford a full-frame body and matching glass.
I am open to a counter argument as to why I should invest more if I intend to use my camera and lenses in the following ways, looking to get educated and understand better -
I use my camera to hike, backpack, or other personal events I want capture. I'd rather spend $400 on a DX camera than a high end smart phone. I am seriously considering the 18-300mm lens which seems to my amateur opinion ideal for my purposes with it's flaws - curvature to the edges of the picture on the low end with less clarity but more light gathering; the telephoto capability lets me leave my binoculars at home and actually get a weight savings. I am thinking about the 35mm 1.4 for the low light situations at the end of the day where I have to depend on natural light and might want to capture a bug or something around my campsite at dusk. So the value of more expensive lenses seem diminished for me since I will be lugging my gear around the woods taking pictures secondarily to the activity I am there for. I'm not a photographer I am hiker that takes pictures.
Here's some of my pictures - https://goo.gl/photos/WkWUkuuU69PYEE8b6When I look at them I remember trying to rebuild my life through interacting with nature and hiking during a hard time in my life... These were on a Canon Rebel that my ex wife owns now...