** What do you want to achieve? ** that the life bar of a specific special player appears above
** What is the problem? ** I do not know how to do it
After that, you should include more details if you have any. Try to make your topic as descriptive as possible, to make it easier for people to help you!
Image of what I say:
(I already have the ui)
If this doesn’t go here or I did something wrong, sorry 
You can get the health of a player, using humanoid.Health and set the GUI text and visual health bar, to this value. This example updates whenever the health of Chosen Player has changed, using Humanoid.HealthChanged:
local ChosenPlr = -- Chosen Player instance
local Humanoid = ChosenPlr.Character.Humanoid
local UiText = -- Path to text
local HealthBar = -- Path to HealthBar frame
local MaxHealth = 100
Humanoid.HealthChanged:Connect(function(NewHealth)
if NewHealth > 0 then
UiText.Text = tostring(NewHealth)
HealthBar.Size = UDim2.new(NewHealth/MaxHealth, 0, 1, 0)
else
print("Chosen Player died")
end
end)
Thank you very much 
,…,.,.,.,.,.,.,.,.,.,.,.,.,.,.,.,.,.,.