Hey @TUNCasiesruocsid! Welcome!
It’s hard to know what to tell you because you haven’t said what the problem is. Are you getting an error when you try to send? How does it fail? Do you get an error, or does it just not get there? Did you check spam?
Here is the standard answer to your “can’t send email” problem, hopefully it’ll help! Troubleshooting email on a new Discourse install