FC analysis with z-maps


I am a graduate student who tries to do the seed-based functional connectivity analysis on resting-state data for the first time. Before digging into the actual data, I wanted to learn and test how it’s done with the classic auditory sample data from SPM site. A colleague of mine suggested me to compare the results from CONN and REST. I struck with many errors but I could come up with z-maps in NIFTI format(for CONN, I only proceeded up to denoising stage). I can’t do the second-level analysis as it is a data of 1 session from 1 participant.

My question is as follows,
What is exactly stored in the z-maps?
What is the best way to visualize this image?
How can I visualize highly correlated areas with specific seeds I selected?

I searched through many manuals and there were many documents on how to transform a t-map to z-map but I couldn’t find instructions on how I can analyze this file. Currently, I have no one near to help me through this so I thought I could get help from here.

Thank you for your time.