One way of doing this is to first start with a clean blender file, then in the 3d view press N to open up the side editing panel. Then scroll to the bottom of the panel, and check the box next to the "Background Images". After opening it, add your reference images (top and side view). Then change the "Axis" to be the correct view for each of your reference images. After that, you will want to add in a plane. After rotating the plane 90 degrees along the "y" axis and setting your view to the top orthographic view, you should now see your reference image with the plane near it. In edit mode, and in wireframe view select you whole plane and move, scale, and rotate it so that it matches up with one side of your knife handle. Then with the whole plane selected use E to extrude G to translate R to rotate and S to scale until you have a rough outline of your knife handle which should look a little like this: It is important that when extruding, and applying your transformations that you have the entire face selected, and not just a row of vertices. After you have done this, you can leave top orthographic view, and apply a subsurf modifier. Don't change any values yet, otherwise it will be difficult when scaling your knife to see the side view. Now go into side orthographic view, and using the values in the side panel translate, rotate, and scale your reference image until it is the correct size of your model. At this point, your height will most likely not match your reference image. It should look somewhat like this: Then scale the knife handle along the "z" axis until the size matches your reference image. Now you will want to adjust the view value on the subsurf modifier to be higher (I used around a 5) to get a smooth knife so your normal map will not look jagged (smooth shading will not do anything in this case). It should look like this: You are now done with modeling, and it is time to make your normal map. First set the origin of the knife to the geometry by pressing Shift+Ctrl+Alt+C. Now press Alt+G to center your model. Now add a plane and scale it up to just be slightly bigger than your knife handle (press Alt+G to center your plane as well). This plane will be what you bake your texture to (it simulates the top of your cutting board). Now go into edit mode with your plane selected and press U to UV unwrap the plane, then press Unwrap. Now open up a UV/Image Editor, and a Node Editor panel. In the UV/Image panel select Image, then select New Image, then set the resolution to something 4k or higher (4096x4096) then click Ok. You should now have a black image. In your Node Editior panel (with the plane selected) add a new material, then add a Image Texture node, and load your new black image into it. Now in the Render section of your Properties panel scroll all the way down and under Bake change the Bake Type to Normal. Then check Selected to Active and change your Ray Distance to 1.000 (you may need to increase this value if your texture dosen't bake properly). Now in order to bake your texture make sure you have your Image Texture node selected in the Node Editor. Then select your knife handle, then Shift click your plane, so that both are selected in that order, then click on bake. Your black image should now be transformed into a normal map of your knife. To save it, in the Image Editor click on Image, and select Save As Image. You are now done and it should look something like this:
Edit: I just realized that you said Bump Map and not Normal Map. You should just be able to convert the Normal Map to a black an white image to get your Bump Map.
I hope this helped, if you are interested in learning more about modeling, or just Blender in general, I would recommend watching Blender tutorials on YouTube. That is how I learned everything that I know today (and it's free). A great person who makes Blender tutorials is Andrew Price, I would recommend checking him out on YouTube if you wish to learn more. Good luck on your cutting board project