How can i do a action but only if there is a part with a specific name in the radius?

Enfaite tu va creer une variable dans ton script, je l'appelle Active. C'est un booleen, vrai ou faux.

local Active = false

Maintenant on va créer une répétition avec while. On va utiliser magnitude poyr trouver la distance entre l'objet et le joueur.

local Active = false

while wait() do
      Active = false
      local mag = (part.Position - Character.HumanoidRootPaet.Position).magnitude
end

Tu va déterminer la distance entre l'object et le joueur.

local Active = false

while wait() do
      Active = false
      local mag = (part.Position - Character.HumanoidRootPaet.Position).magnitude
      if mag < 5 then

      end
end

Maintenant tu va changer la valeur de Active sur vrai

local Active = false

while wait() do
      Active = false
      local mag = (part.Position - Character.HumanoidRootPaet.Position).magnitude
      if mag < 5 then
           Active = true
      end
end

Ajoute cette ligne dans ton Userinput

UserInputService.InputBegan:Connect(function(Input)
    if Input.KeyCode == Enum.KeyCode.E and not climbing and Active then
        Climbing = true
        ClimbTrack:Play()
        Climbing = false
    end
end)

Here's what I would do. With a model of parts which include the "grab" parts I would run a function which would go through each one and check to see if it was near the player.

If there are many 'grab' parts in this model, you could create a way to separate which parts the function runs on. But in most cases we won't need this.

local UserInputService = game:GetService("UserInputService")

local climbing = false

local Player = game.Players.LocalPlayer
local Character = game.Workspace:WaitForChild(Player.Name)
local Humanoid = Character:FindFirstChildOfClass("Humanoid")

--my variables
local armLength=3 --length of radius
local grabParts=workspace.grab --change to model of grab parts

--making grab check function
function grabRangeCheck()
    --go through each grab part
    for _,grab in pairs(grabParts) do
        --if close by then return the grab part
        if (grab.Position-Character.HumanoidRootPart.Position).Magnitude<=armLength then
            return grab
        end
    end
end



Climb = Instance.new("Animation")
Climb.AnimationId = "rbxassetid://3284607610"
ClimbTrack = Humanoid:LoadAnimation(Climb)

UserInputService.InputBegan:Connect(function(Input)
    --added range check function
    local grab=grabRangeCheck()
    if Input.KeyCode == Enum.KeyCode.E and not climbing and grab then
        Climbing = true
        ClimbTrack:Play()
        Climbing = false
    --run extra code for what to do with the grab part under variable "grab"
    end
end)

And tada! The animation will only run if a grab part is nearby.

Extra

If there are a lot of grab parts you could create a parameter for the check function to run the for loop for a certain 'map'

grabRangeCheck(mapname)

and in the function

for _,grab in pairs(>mapname<) do