hello najeeb.. we use can to say that something is possible or that somebody has the ability to do something. we use could to say that somebody had the general ability or permission to do something. in these sentences could is more polite than can. noramlly could we use for Request.

actually, KK/Jennifer is right... "Can" is used to express the ability of someone to perform a thing. "Can you tell me where is the place?" is somewhat saying "will you lead me to that place?" or "will you show me the way?" "Could" is used as requests polite permission. "Could you tell me where is the place?" is like saying "Please tell me where is this place." :)

"Can you tell me where is the place?" - It is asking whether the person has the ability to tell where is the place. "Could you tell me where is the place?"- is used when making a polite request

how can i use the being?

Hello Najeeb, Could expresses possibility ,so since you don't know if the person you are asking is able for sure to tell you where the place is , you use "could" . "Could you tell me where the place is ?" On the other hand "can" might express permission ,you would be using it to ask someone for permission to do something : " Can I tell you where the place is ?"