Click on the 'Daily Tasks' icon from the War Thunder in-game hangar.
On the menu that opens, click on the 'Warbond Shop' icon in the bottom right corner.
You can now view the range of Warbonds available by clicking on on the various icons.
Purchases can be made with the 'Purchase' icon in the bottom right corner.
Battle tasks: These individual tasks bring variety to your gameplay and prevent situations where all the players in a battle try to complete one specific task, effectively ignoring mission objectives that are needed for a victory. They are available for players that have reached the 3rd rank of any nation. On completion, players will receive Silver Lions, and Warbonds - a special in-game currency with their own specific shop, where you can purchase many different items.