How to allow RPlayers into RDoors ????

local ps = game:GetService("PhysicsService")
ps:CreateCollisionGroup("BDoorsGrp")
ps:CreateCollisionGroup("RDoorsGrp")
ps:CreateCollisionGroup("BPlayersGrp")
ps:CreateCollisionGroup("RPlayerssGrp")

local bDoors = workspace.BDoors:GetChildren()
local rDoors = workspace.RDoors:GetChildren()

local function setDoorColGrp(doorTbl, group)
	for i=1, #doorTbl, 1 do
		ps:SetPartCollisionGroup(doorTbl[i], group)
	end
end

setDoorColGrp(bDoors, "BDoorsGrp")
setDoorColGrp(rDoors, "RDoorsGrp")

local function setPlayerColGrp(char, group)
	for i, child in ipairs(char:GetChildren()) do 
		if child:IsA("BasePart") then
			ps:SetPartCollisionGroup(child, group)
		end
	end
	char.DescendantAdded:Connect(function(desc)
		if desc:IsA("BasePart") then 
			ps:SetPartCollisionGroup(desc, group)
		end
	end)
end

local function onPlayerAdded(player)
	player.CharacterAdded:Connect(function(char)
		if player.Team.Name == "Blue" then
			setPlayerColGrp(char, "BPlayersGrp")
		else
			setPlayerColGrp(char, "BPlayersGrp")
		end
	end)
end

game.Players.PlayerAdded:Connect(onPlayerAdded)
ps:CollisionGroupSetCollidable("BDoorsGrp", "BPlayersGrp", false)
ps:CollisionGroupSetCollidable("RDoorsGrp", "RPlayersGrp", false)

How do I make where RPlayers (Red Team) can collide with RDoors?

I think the best approach would be to check the players team and set the door collisions on the client.

In a local script in StarterCharacterScripts

Code example:

local Players = game:GetService("Players")
local player = Players.LocalPlayer

local bDoors = workspace.bDoors
local rDoors = workspace.rDoors

local function setSolid(doors, isSolid)
	for _, door in pairs(doors:GetChildren()) do
		door.CanCollide = isSolid
	end
end

local function InitializeDoors()
	if player.Team.Name == "Blue" then
		setSolid(bDoors, false)
		setSolid(rDoors, true)
	elseif player.Team.Name == "Red" then
		setSolid(rDoors, false)
		setSolid(bDoors, true)
	end
end
player:GetPropertyChangedSignal("Team"):connect(InitializeDoors)
InitializeDoors()