Some further clarification of terms. `Rendering' simply means displaying the model or scene you're building, and all modelers today render in real time to some extent while you're working so you can see what you're doing. However, this will be simple wireframe or with basic shading.

For the final image you need a raytraced render if you want photo-realistic output. This produces a view with correct lightsource effects, reflections and refraction based on all materials and lighting used on the 3D content in the scene. Povray is a good renderer but isn't a modeler. Metasequoia is a good modeler, but only has basic non-photorealistic rendering. Expensive software combines both and usually has animation as well.

For attaching textures (like bark on a tree model) you'll need to learn about UV mapping, which is a complicated subject in its own right.

Best advice is to get all the free apps and demo versions and see how you get on with them. You can, in fact, do a hell of a lot with the free stuff.