There are a few different ways that you can remove stray hair in Photoshop, and which method you use will depend on the image that you are working with. If the stray hair is not too noticeable, you can use the Clone Stamp tool to cover it up. Simply select the Clone Stamp tool from the toolbar, and then click and drag over the area of the image that you want to clone. As you drag, the cursor will leave behind a copy of the pixels that it is sampling.
Release the mouse button when you have covered up the stray hair. If the stray hair is more noticeable, you can use the Spot Healing Brush tool to remove it. Simply select the Spot Healing Brush tool from the toolbar and then click and drag over the area of the stray hair. The Spot Healing Brush tool will automatically clone neighbouring pixels to cover up the stray hair.
In conclusion, there are a few different ways that you can remove stray hair in Photoshop. Which method you use will depend on the image that you are working with.
If the stray hair is not too noticeable, you can use the Clone Stamp tool to cover it up.