In my opinion there's a huge variety of kits, all the way from "shake the box" to completely unbuildable.
This even varies within one manufacturer. Here the internet can truly be your friend, as a simple search using the kit subject, manufacturer and scale will keep you busy for hours.
Depending on your subject, some manufacturers are usually pretty dependable. Tamiya immediately comes to mind. With very few exceptions, their kits go smoothly, the instructions are pretty clear and the detail is excellent. However within that line, research is worthwhile because some of their kits have been around for a long time and show their age. But it's hard to find fault with anything they sell, at least short of the experts and their various issues.
Italeri is more problematic. One reason in particular is that over the years they've reissued quite a few kits originally sold by other companies. A good example would be their recent SM.81 aircraft. It's a reissue of the old and at the time only available model of that aircraft, by Supermodel. It was a good enough kit, but the reissue includes new fuselage halves with outstanding rib and fabric detail, and excellent decals. That plus the box art and information included make this kit outstanding.
I don't know why I feel in a position to give you advice, but that's not gonna stop me. Keep it simple. Don't spend too much on a kit at first. Be discriminating and focus on building them, not just buying them. There are advanced modelers on this forum who have probably never spent more the $ 25 on a Monogram kit, and they know who they are, that can turn out excellent results with craft and ingenuity added.
Build a dozen kits in the $ 15- $25 range until you have a feel for what companies you like, and your scale and subject.