Based on the blocks the drone has been built with (and where they are), the following abilities can be used by the drone:

Arrow Launcher

When a dispenser is built facing forwards (and not blocked), the drone will automatically shoot arrows at nearby enemies.

This will not consume any arrows, and is always active.

Light

A strong light block anywhere on the drone will allow it to glow. When moving around, the drone emits a light in the world.

Melee Attack

When a block that deals damage on contact (a cactus or a magma block) is built on the front of the drone, the drone can attack entities.

It'll automatically fly towards nearby hostile enemies, and it'll also attack other mobs after the player has attacked them.

Mining Support

The drone can assist the player in mining blocks. To do so, build a drill block on the front of the drone. When the player starts to destroy a block, they drone will fly towards the block and then also start breaking that block, making mining a lot faster.

Item Pickup

The magnetic properties of a lodestone block can be utilized by the drone to pick up nearby items and bring them to the player.

Laser Beam

Similar to the arrow launcher, a beacon block on the front also allows the drone to attack nearby enemies. However, instead of a simple arrow it'll shoot a massive beam at the target.

Thrusters

The mod adds new drone rotor blocks, in 3 variants: Wooden, Iron and an Ion Thruster. If you want to keep a vanilla aesthetic, you can also use trapdoors as basic rotors.