if more than ten players touch part then print("Hello") ?

local touchingPlayers = 0 --make a local variable of the number of touching players

local function checkPrint() --make a local function that checks number of touching players
    if touchingPlayers > 10 then 
        print("hello")
    end
end

part.Touched:Connect(function(touchedPart)
    local player = game.Players:GetPlayerFromCharacter(touchedPart.Parent) --if touched part is child of player's character then this will return player. if not it will return nil
    if player then
        touchingParts = touchingPlayers + 1 --if player then add 1 to number of touching players
        checkPrint() --fire checkPrint function to see if there are 10 players touching the part
    end
end)

part.TouchEnded:Connect(function(touchedPart)
    local player = game.Players:GetPlayerFromCharacter(touchedPart)
    if player then
        touchingPlayers = touchingPlayers - 1 --if a player has stopped touching the part, subtract 1 from number of touching players
        checkPrint()
    end
end)

Let me know if this works

I recommend storing each player name that has touched the part into a table and then checking if the table has a length of more than 10. Doing it like this, you can prevent the same player from being added to the table and incrementing the number due to multiple interactions with the part.

Example (Server Script)

local TouchedPlayers = {}

script.Parent.Touched:Connect(function(hit)

    local Player = game.Players:GetPlayerFromCharacter(hit.Parent)

    if Player then
        if not table.find(TouchedPlayers, Player.Name) then
            table.insert(TouchedPlayers, Player.Name)

            if #TouchedPlayers > 10 then
                print("Hello")
                table.clear(TouchedPlayers)
            end
        end
    end
end)