hello all quick question

[Mike C]

I just found a Rolex watch in my deceased father in laws stuff my wife was left all this stuff and we were going through it and low and behold there it was . it looks older but the funny thing is it says date just on it but has the day also . plastic crystal and isn't working does this take a battery ? or self winding ? it is two tone silver and gold band with silver face gold hands and slashes were #s should be . how can I tell if this is the real thing ? any insight will be greatly appreciated
Mike