Hy. I use blener and I have a dubth : 1)How create a bumpmap with blender?I read that must be install a plugin , is true? 2)What plugin do you advice to me? 3)And for translate the bump map to a normal map? 4)Is indispensable create the bump map for generate a normal map?

1) You can create normal maps with baking in blender.
3) To convert between height maps(=your bumpmap?) and normal maps you can use tools like xnormal.
4) Bumpmapping refers more to a technique than to a texture kind. You can do "bumpmapping" with height maps or with normal maps. To create a normal map you could either model a height polymodel and "bake" it to a low model texture (see 1.) or you can create a heightmap (=your bumpmap) and use special tools like xnormal (see 2.) to generate a normal map from it.

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Ashaman