Both telescopes are optimized to work on the wavelength range of the infrared. However, the JWST has a very narrow and detailed field of view. Instead, the Nancy Grace Roman will cover a very broad patch of the sky. One way to understand this is that the science goals of both telescopes are different, and thus, their coverage has to adapt to these observational needs.
The JWST aims to recover deep lines of view of the sky. On the other hand, the Roman will provide us with the "Big Picture". It will complement other wide galaxy surveys run from the ground, such as DESI or the upcoming Vera Rubin Observatory.