This is a great question. Regarding your eyebrows, you need to ask yourself if you are missing texture or density. If you have texture but lack density, then consider microblading. If you lack texture, then consider an eyebrow transplant. The downside to an eyebrow hair transplant is that the hair continues to grow and needs maintenance throughout life to trim.
With your eyebrows sparce since birth, knowing it was always there, the best treatment for this is a eyebrow transplant