How to make a player stuck to a part?

I don't have a clear understanding on what your goal is here. But to get to your main question, on how you can make a player stuck to a part using a script it's pretty simple

local Players = game:GetService("Players") -- Getting the players service which isn't necessary but i intend to do so most of the time

local player = Players.LocalPlayer -- Getting the player

repeat wait() -- Repeating wait() and not allowing the code below this to execute until the player has loaded so the script won't cause any errors if let's say he left early

until player.Character

local char = player.Character

local humRootPart = char:FindFirstChild("HumanoidRootPart") -- We're using the HumanoidRootPart as a position for the player since that's the part welded to majority of the bodyparts

local part = nil -- Put the part you want the player to be stuck on here




local function stickPlayerToPart()
	
	humRootPart.Anchored = true
	
	while wait() do -- We're putting this in a while loop so the player will countinuesly be stuck on that part no matter if that part changes position. This is optional depending if the part will change position.
		
		humRootPart.CFrame = part.CFrame -- Now we're applying the player's CFrame (HumanoidRootPart), to the part's CFrame
		
	end
	
end


stickPlayerToPart() -- Calling the function, you may want to call this function at different times, but i'm just showing you how you can acccomplish what you asked for

If you're not completely sure on what CFrame is as shown in the lua code, here's a better understandinng on what it is: