var/lRooms=list()
mob
    Stat()
        statpanel("Rooms")
        if(statpanel("Rooms"))
            for(var/obj/room/O in lRooms) stat(O)   //displays all rooms in a tab
    verb
        Create_Room()                                               //I was unsure what you meant by button
            var/Na=input("What is the name of the room?")as text    //If you wanted a literal button you use the Click()
            choose_MA                                               //procedure for a object and then redeclare this as a proc
                var/MA=input("What is the max amount of people who can join?")as num//instead of a verb
                if(MA>5)
                    alert("A max of 5 people to a room!")
                    goto choose_MA
                else if(MA<2)
                    alert("A minimum of 2 people must be allowed to join!")
                    goto choose_MA
                new/obj/room(Na,MA)
obj
    room
        icon='Rooms.dmi'
        var/amount
        var/max_amount
        New(var/Na,var/MA)
            ..()
            name="[Na]-[MA]"      //the name is set to the text provided by the user + the amount chosed by the user
            max_amount=MA         //upon creation sets up max amount and name
            lRooms+=src           //then adds itself to the global list of rooms currently "open"
        Del()
            lRooms-=src
            ..()
        DblClick() //Assumes you double click the "room" button to enter
            if(amount>max_amount)
                usr << "This room is full!"  //If it has more than 5 people in it then you cannot join
            else
                usr << "Welcome to [src.name]!"  //otherwise welcomes you to the room and increases amount by 1
                amount+=1                       //you need to make sure to decrease the amount by 1 when they leave
                //This is when the mob enters the room successfully