step in my life
Your career, not your life. The masters course only relates to your career opportunities. These opportunities are what relate to your life. Therefore, it is the career that must be advanced. Do not refer to your private life in the discussion.
chance to join
Join as what? Remember that internships are not as impressive as they sound in these masters course applications. They give more weight to professional experience and notable accomplishments. Be clear about these references. The screener may not give any weight to this presentation when there is a lack of clarity in the reference.
acquiring the skills necessary to work in the field of research and development
In connection to what specific field? Do not cast a wide net. The screener needs specifics, a definite career path that will dictate how the masters course learning will be used and its relevance to the career considerations.
The overall motivational letter does not carry any sense of conviction or refer to any strong specifics that would make the applicant a notable consideration for the grant or acceptance to the university. It is too vague and lacking in career related discussions.