True Anomaly of Circular Orbit

How would you calculate the true anomaly of a circular orbit (e=0)? I'm trying to design an orbit for a mission on STK and so I'm not sure what the eccentric anomaly (in order to calculate true anomaly) would be since it's not a question about the orbital element at a particular time.

Then just use $$𝜈=𝑀=2𝜋/𝑇$$