Hi Lubica, 

Welcome to Box Community and glad to assist! 

For you to create a password, you can reset the password for your Box account, follow this process:

1. Visit https://app.box.com/reset and enter the email address associated with your Box account.
2. Check your email, you will receive an email with a link to reset your password.

• • Password reset links sent via email expire 3 hours after they are sent. If you need a new link after your current one has expired, visit https://app.box.com/reset to have another link emailed to you.
  • If you do not receive an email from Box for this password reset, check to see if your Box account is associated with that specific email address or another email address.
  • Also, check your spam folder in your email client for this email.

Thanks for posting!