new account not receiving or sending emails

Hi i have just made set up an account and had a new email address also . However i am trying to send emails but they are not sending, or should i say they are not being received and the addresses are correct. Not only that but i can see that i have 3 emails on my new emails address and i can not open them ........ Please help, i have to contact many people asap , your help would be priceless

Thank you in advance Deb