Is there a staking reward for Nillion, how does this system work and what are the requirements?

There will be 2 staking options;
The light knot has minimum staking requirements,
Full Nodes will be subject to a higher minimum staking requirement, given their enhanced role in the network.

Nodes that are unable to meet the minimum staking threshold due to withholding or withdrawal of the staking deposit
cannot participate in network functions or store network data up to a minimum level. The staking token deposit is restored to users.

Source: DocSend Page 39-40 Node Staking Mechanics Chapter.