[Maria-developers] [beginner] how can I assign an existing ticket to myself?

Hello, I wanted to contribute something to MariaDB, so I signed up to Jira, but how can I assign an existing ticket to myself? [programming experience]: I have been programming for over 10 years but recently using Java, Python, Node.js at work and C ++ is a little played a few years ago. [knowledge of the MariaDB source] I just started reading the code recently and I am almost an amateur. [how much you know about using MySQL/MariaDB] I use MySQL for WordPress backend as a user and I use Oracle for work, so I have knowledge of general RDBMS, but I do not have deep knowledge specific to the products. Thanks, Takashi Sasaki