Hi , There are many reasons for identity crises and feeling unsure about who you are like,unhappy childhood, present living situation, anxiety,stress.unhappiness etc.When you are not satisfied with life, your needs are not met you will feel incomplete.
If you feel like you don't know who you are ,spend some time alone getting to know yourself better
Next Steps
Consult a psychologist for psychological assessment and getting help to deal with underlying causes and treat any other psychological problems like anxiety, depression etc
Health Tips
Focus on your strengths
Challenge yourself
Start making decisions
Mindfulness meditation