Add your Hero to your Team to use Weapons in battle and level your Class.
To add your Hero to your team:
- Enter the Troop menu
- Select the Weapon Tab
- Select the Team you'd like to put your Hero in
- Either select the Weapon you'd like your Hero to use and then select "recruit" or drag and drop the Weapon into your Troop list.
The article linked here explains how to equip a Hero Class to power up your Hero further in your Team.