Copy and paste this web site. It has a video to watch for different nail issues.
Then choose www.WebMD.com/Skin_&_Beauty
Hopefully you are not a smoker, this will cause a yellow tinge.
Soaking fingernails in warm olive oil for about 20 min daily should help reduce the yellow color and also strengthen your nails and is great for your nails health.
Take a biotin supplement.
If you like wearing nail polish, always put on a base coat first to help protect your nails and also will help the nail polish last longer.
Other people asked questions on various topics, and are still waiting for answer. Would be great if you can take a sec and answer them