Did you know that you do not need an expensive, speciality macro lens to shoot macro photos?
The image below is a full frame (not cropped) photo taken with a 70 mm lens at about 15″ from the flower. This is the closest you can get with this lens and keep your subject in focus.
However, if you add an inexpensive extension tube, you can get much closer. The image below is also a full frame (not cropped) photo taken with the same 70 mm lens with a 36 mm extension tube added between the camera and the lens. I was able to get to within a few inches of the flower.
Extension tubes are available as a set with multiple extension rings of varying size or one at a time. As with most camera accessories, manufacture-brand extension tubes are more (often much more) expensive than third-party brands.
If you buy extension tube, make sure they support automatic focus. And, or course, if you get a third-party tube, make sure it matches your camera mount (Nikon, Canon, Sony, etc.). I used a Kenko brand extension tube on the above photo on my Nikon camera. A set of Kenko 3 extension rings cost about the same as one Nikon-brand extension ring!