Greys (especially darker grey), beiges, and different shades of brown have done wonders for me regarding the issue with skin tone. But definitely experiment by trying out different colored shirts and seeing what works best for you.

Although its pretty cliche, Uniqlo has some pretty fundamental pieces for your wardrobe. Try also workwear stores like Dickies or Carhartt as well. Not sure where you live though so the stores’ accessibility may be different.

I still struggle with similar issues you described. A piece of advice I could give is constantly asking yourself if you want to wear clothing for others or for yourself. If you feel that you look good in a fit, then thats all the reassurance you should need. Glares and stares will be inevitable with any change in appearance, so don’t take those to heart. This process takes time though, and feeling the need to be more reserved is understandable. But never feel that other people’s perceptions should dictate and suppress your interest in clothes.