Follow these steps to upload your theme in Drupal:
STEP 1: Log in to your administrator Dashboard in Drupal.
STEP 2: From the to menu of dashboard, navigate to Appearance and Click Install new theme.
STEP 3: As you click Install new theme, you will see a browse window as shown below. Browse your theme and press “Install Now” button.
STEP 4: After the successful installation of your theme , a confirmation message will display as following. Now Enable the theme by selecting your theme from Enable newly added themes.
STEP 5: After enabling the theme, you are done and may visit the site to see how it looks on browser.