What can I do to look more masculine and attractive? (Photo)

You don't appear to have a lack of masculinity in the face.  As far as the nose--straightening it, decreasing the size of the tip, and decreasing the projection (prominence of the tip from the face) would likely be beneficial.  Perhaps if anything for masculinity in the nose, you could consider augmenting the bridge a very small amount, but this is by no means critical.I hope that helps.

I agree that the septum is a component that is bringing imbalance to your nose as it deviates the middle third to the left. If it bothers you, the nasal tip could be refined as well. One of the biggest parts that I look at regarding masculine facial features is the chin projection in relation to the nose, but that could be assessed better with lateral (side) photos. The key is to have all if these features fit the rest of your face and maintain a natural appearance.

I'll agree that your septum appears moderately deviated. This could be improved with surgery.  But what is the need for the testosterone. At 20 years old, your levels should be close to maximized. Do you have a documented deficiency? Is there real justification to warrant supplementation and who is suggesting this? I would doubt there is medical justification for this and therefore I would also hesitate recommending surgery to "masculinize" someone your age.  I recommend a healthy diet and work out, give your body time to achieve your goals!