The question has been edited to contain a link to high resolution version of the wood image. It's so sharp that one can try more tricks and to straighten the wood texture (not asked, but I guess it's useful).
Straightening
Krita has G'MIC filter pack included. Its deformation filter Quadrangle at least is simple and straightens the pattern substantially:
The result:
But the color and brightness variations need still fixes. The apparent large area brightness variations very likely should be faded. There's an older answer where the job is done manually. That's, of course, a good method if one wants full control. A fast way is to use filtering - slow changes can be faded with high pass filtering. It destroys colors, so you can as well desaturate the image.
Duplicate the image layer and apply Filter > Adjust > Desaturate.
Now you can fade slow brightness changes by applying Gaussian High-pass Filtering. It's placed in the edge detection filter group:
High-pass filtering reduces contrast. The darkest and brightest shades are far away from black and white. In theory it's a good thing if you want to colorize the image to a single hue color. We skip it. We increase the contrast with Filter > Adjust > Levels so much that there's black and white pixels, too:
We are going to use the result as a transparency mask to make controlled mix between the dark red color and lighter more yellow color. That unfortunately will remove nearly all apparent surface roughness. You can prepare to insert it back in a controlled way by making an embossed version of the desaturated and high-pass filtered layer. Duplicate, rename the layer to Embossed and apply Filter > Emboss > Emboss with variable depth:
Close the embossed layer temporarily. Insert 2 new paint layers below the low-pass filtered layer. Give to them names "Bright Top" and "Dark Bottom". Fill them with the brightest wanted color (=Top) and with the darkest wanted color. I picked those colors from your image.
Select the low-pass filtered layer and apply Layer > Convert > To Transparency Mask and move the generated mask inside the "Bright Top" layer:
The result can be made more luminous with brighter top color (pick from the color wheel and fill with the paint bucket):
The result looks quite flat. You can add surface roughness by making the embossed version visible. Let the layer have blending mode overlay and reduce the opacity:
The opacity is 40% which is too much, I guess. It may look too offensive because it lightens already bright pixels. But you got the idea.
You can also experiment with different blending modes than Overlay and by applying Curves or Levels adjustment. The next (weird) curve keeps the heavy roughness, but it doesn't make the already bright pixels brighter:
The opacity is now 100% and the effect is controlled by drawing the curve. When it's confirmed by pressing "Create Filter Mask" it can be readjusted later. It's quite the same as an adjustment layer in Photoshop with "the next layer only" -switch ON.
There's still one place left for experiments. The transparency mask which controls the mix between the dark and bright color can be edited. Here is applied Filter > Adjust > Color Curves. The change is substantial:
Unfortunately I have not figured out any easy way to make it readjustable (except by having a non-adjusted copy). But one can use a workaround. Mixing 2 layers with transparency mask can be replaced by applying Filter > Map > Gradient map to the desaturated + low-pass filtered + contrast boosted version. It makes possible as well weird and mild colorize. Here's an example (no roughening with embossing in this time):
Gradient map can be inserted as Filter Mask, so it's readjustable. It looks simpler and much more flexible than the mix between 2 layers version. The only drawback is the extreme sensitivity of the gradient map dialog to insert and move the gradient stops. But that can be defeated by practicing a while.
