Can someone tell me how to do this?

Can someone tell me how whenever I click on a part(already has clickdetector) it will change my shirt and pants to certain ID’s?

Thanks!

Well you can do this on click:

you can store your shirt and pants if you want a certain ID in a variable like so:

local coolShirt = 1231231312
local coolPants = 123165473

Then you can use the HumanoidDescription system to apply clothing to the humanoid which is the person who clicked

Example code from Dev Reference API (Go check it out) for applying new Sunglasses and a new torso.

local humanoid = player.Character and player.Character:FindFirstChild("Humanoid")
if humanoid then
	local descriptionClone = humanoid:GetAppliedDescription()
	-- Only one torso is allowed
	descriptionClone.Torso = 86500008
	-- Multiple face accessory assets are allowed in a comma-separated string
	descriptionClone.FaceAccessory = descriptionClone.FaceAccessory .. ",2535420239"
	-- Apply modified "descriptionClone" to humanoid
	humanoid:ApplyDescription(descriptionClone)
end