I still own a K100D super, it was my first DSLR.
I started macro using the standard 18-55mm lens and a magnifying glass. This very basic setup can give good results:
Several months later, I bought my first macro lens, a Cosina 100mm macro F3.5. It can reach 1:2 alone and 1:1 if you use the dedicated close-up.
Then I bought one 1.4x teleconverter and 2 extension ring kits, here is a setup enabling about 5:1:
Later, I bought a Tamron 90mm macro (model 52B), my first Tamron. Then I bought (and sold) many other macro lenses.
I currently own 6 macro lenses from 60mm to 180mm, they reach 1:1 to 5:1, I love each one.
I sometimes revert a wide angle lens (35mm e.g.) and maybe add one or two extension rings.
I also can add a close-up to a telelens (the Pentax DA* 300mm F4 performs well if you use it with a Nikon 5T or 6T close-up).
To summarize, the possible setups are endless. You just have to choose a lens according to your needs and you can add
-bellows or extension rings if it is a short focal,
-close-up if it is a long focal.
You also may try microscope lenses or enlarging lenses, it is weird but it works:
Practically, insects and bugs prefer longer lenses because the working distance is longer. So 100mm to 200mm is a good range.
There are lots of topics about maco lenses over there, you can read them in order to make your choice.