27 with receding hairline since early 20s, Fue Hair Transplant candidate?

The Hair transplant is possible at this stage: you are Norwood 3. It will be possible to take 2500-2800 grafts from the donor area to restore and lower the Hairline  with maximum density possible.  The hair loss might continue in the future and you might need a second hair transplant. The density level of the donor area is good.  The Finasteride and the PRP Treatment is recommended to slow down the hair loss. In person consultation will be more helpful.

The goal of a hair transplant is to provide fuller coverage while preserving a natural appearance. An assessment takes into account such factors as the apparent thickness and curl of your donor hairs, the color contrast between your scalp and hair, your hair loss pattern, your age, and many other factors. The state of the art technique is FUE (follicular unit extraction), performed with a hybrid blunt punch that minimizes graft transection while allowing for the use of the smallest possible punches to minimize donor site scarring while maximizing regrowth. I would recommend an FUE procedure of 1200-1400 grafts to fill in the frontotemporal areas. The key is to provide you with an improved hairline while also saving donor hairs for the future as your hair will likely continue to thin over time. Gary Linkov, MD
Hair Specialist
Manhattan

Hello.
Around 2800-3000 grafts will be enough to restore and fully cover your hairline. The procedure can be done by Unshaven Sapphire Fue Method as well. About usage of Fin, if you stop taking it after having the procedure you can lose hair on other areas and it can look weird after transplanted hair grows.

Based on the photo provided you have an excellent donor region to harvest grafts from. Its unclear what would need to be done without seeing additional photos.