I think you did a good job, 1 thing that stand out a little bit to me me is the ear part. On the inside of the ear you outlined those small vertical shapes where I think in would be better to fill it in in black only instead..does that make sense? Overall it does seem pretty good to me, your drawing might just be slightly larger than the original but other that than it's just details different. Maybe try making a circle first as a basic reference point as it does seem like a spherical ball. Hope this helps lol

It's the accuracy drawing guide

For the 3rd one in the head I think you could erase the vertical center line or make it lighter since it makes it seem like the head is facing us which is weird lol For the 4th one maybe make the head slight larger and shorter to make it seem like it's tilted backwards more, also it does not seem to follow the line you made for the spine properly, seems too bent sideways. The 6th one I think the shoulder line is tilted a little too much. Maybe make the left shoulder go up a little bit. This applies in general for a lot of these unless you're trying to exaggerate the shoulder line angles on purpose. There a few other things I think can be improved but overall seems pretty nice ;) Also I did not comment on limbs since you said you're focusing on torso and head but I think there's room for slight improvements there too. For the arm placements. Hope this helps :)

I think the belly pops out a little too much, erasing the part of the outline below the elbow and connecting it to the hips I think would help