I think I have a pale face, at the same time I have a hg of 12 is it related and if so what food is essential to increase my haemoglobin?

Iron containing food. First off, your hemoglobin level is normal. But, iron helps make hemoglobin. Iron containing foods include: leafy greens, liver, beef, turkey, and beans.
Probably not related. Hemoglobin is the oxygen-carrying protein found in red blood cells. The normal range varies by age and gender, but 12 is pretty close to normal, and not likely low enough to cause paleness, unless it is a big change for you. If you have a low hemoglobin, i would find out why. The most common reasons are nutritional (low iron/protein) or blood loss from menses, but there could be serious causes.
Pale face. There are many reasons that could cause your problem. A HGB of 12 is probably normal so that would not cause it. Be sure your are living a healthy life style, with fresh foods and veggies. No smoking or recreational drug use. Are you on any medications? Get some sunshine on your skin frequently but do not burn.