How I can add another language in my learner or tutor profile?

You can add additional learning languages to your profile at any time by clicking the red "Schedule A Lesson" button in the header of your profile (while in Learner mode) and then clicking the red "Request Top 5 recommended tutors" button. This will take you through the flow of requesting tutors for a language, allowing you to input any language you are interested in learning and it will be added to your profile. 

You can also add languages you are interested in learning in Exchange Lessons to your profile from your Tutor Application. You can add additional teaching or exchange languages to your profile at any time from your Tutor Application. You can open it from the "Tutor Application" tab of your Preferences page (while in Tutor mode).