I have what i think is a nigerian phone number that i need to call.

Firstly i have what i think is a home number it starts with 014 and has 9 digits,  the second is i think a mobile number is starts with 080 and has 11 digits. 

Is this correct for nigerian numbers and what do i need to call from overseas to contact these numbers.

I do not know about the numbers. But to call any country, you need to dial the international dialing prefix for your country, then the country code and city code you want to call. So, for example, to call a Nigerian mobile(08038889999) from the US, I will dial 0112348038889999. 011 is the Intnl' dialing prefix for the US. If you are using a GSM phone you will dial +2348038889999. The network will automatically prepend the number with the international dialing prefix for whatever country you are calling from.