If you cannot use your WordPress password to login to backend, you can reset it directly in phpMyadmin.
See how to login to control panel and phpMyadmin
Once you have accessed to phpMyadmin, select your database in the left and click “Browse” at wp_users table
At the row of user click “Edit” and at Field user_pass, Select Function = MD5 and enter your login password.
Then try to login to WordPress backend again using your password that you have reset.