When it comes to understeer, there are a few things you can do in Forza Horizon to help alleviate the issue. One of the most important things is to make sure your tires are properly inflated. This will help with grip and prevent the tires from slipping on the pavement. Another thing you can do is adjust your suspension settings. This includes both your spring rate and damper settings. By stiffening up your suspension, you'll be able to reduce body roll and keep the car more level as you enter corners. Additionally, you can try changing your differential settings. A lower setting will increase traction and help to keep the car from plowing through corners. Finally, remember to brake in a straight line when entering corners!