Q: outlook email problem

I created a new email account today through outlook.  I went through the process of adding the account to the mail.  I can receive but not send emails.  I did all the trouble shooting I could find online.  I checked that everything was entered correctly and even deleted and re added the account.  Still not able to send emails. On my iPhone it works fine but not on my macbook. They go to the outbox and never send.  Is outlook email not a good option for a mac or what am I doing wrong?????