Scaling and polishing will remove stains Filling will remove cavities In your case both has to be done

Hello, these indicate starting of decay, I suggest you to first go for scaling procedure, get yourself evaluated and get them filled. Looks like the decay has just started and can be stopped here itself by filling but still evaluating is important as sometimes the decay looks less from outside and is much deeper inside Also, get your already filler tooth also evaluated

Hi, these black dots indicate beginning of cavity. You need to get filling done. Also note that your oral health looks poor.