DKP is not a game stat. It is a score your kingdom's leadership makes up to rank who actually fought in KvK, usually built from T4 kills, T5 kills and dead troops, since raw kill points can be farmed cheaply.
A typical formula looks like: T4 kills x 10, T5 kills x 20 to 30, deads x 50 to 80. Every kingdom picks its own weights.
Kingdoms often set a requirement scaled to your power, for example a DKP or kill target equal to a multiple of your power, and governors who miss it can be asked to migrate, lose access to rewards or be zeroed.
Ask your King or council for the exact formula and your target before KvK starts, and screenshot your stats at the start so your gains can be tracked.