The formula used: At time t, the current in the LR circuit is given by

Where I is the Current

is the emf

R is the resistance

L is the self-inductance

At time the current is given by

At t=0, the current in the circuit is zero.

The magnetic field energy in the inductor is given by

Current is zero at t=0, So magnetic field energy is also zero.

Therefore, power delivers by the battery is also zero at t=0.

At t=0, the current is on the verge to start growing in the circuit. So there will an induced emf at that time to oppose the growing current.

In the LR circuit, at time t=0 there will be an induced emf in the inductor. Exactly at t=0, the current, magnetic field and power delivered by the battery are zero.