Hi everybody! Need help with color matching!

Hi everybody! I would be grateful if somebody can help me!

I also thought about buying a color ring and to let an aerea to grow some hairs to have some samples . Can I ask:

-Is any color ring good or color code-actual color match may vary between different sellers?

-I was thinking to let an area of 3x3-3x4 cm behind the ear grow for 2 months and since I go around bald I was thinking to cover it with a band-aid/pharmacy patch when i go out. Do you think it's a good idea?

https://preview.redd.it/7z2yfsai99ng1.jpg?width=641&format=pjpg&auto=webp&s=fa1ddf09dd80a02a1fbf95f9d84f24ef01220791

https://preview.redd.it/e9nqatai99ng1.jpg?width=506&format=pjpg&auto=webp&s=9eaae5917e81163253e25b8be82449a8a62eabb3

https://preview.redd.it/cj5zcyai99ng1.jpg?width=825&format=pjpg&auto=webp&s=3f44787520406be43cfc686e991fa8960373be1f

Thanks in advance everybody! Glad to hopefully join the community!