In addition to the caution and information in the above replies, I'll suggest reading
https://zeromanual.com and see what you can learn. The information is available there to figure out what you actually need to know.
One short answer that may be helpful is that almost all of the bike is de-energized after keying the bike off, because a contactor disconnects most of the bike's circuits from battery then.
There is still some residual charge in the controller and connected chargers for up to 10 minutes after that, and there are some paths out of the battery that keep parts of the bike energized, but none of that is physically accessible by default. And the Zero pack voltage is at or less than 116V so it's not as dangerous as most EVs.
Zero's systems are reasonably safe. But if you don't know how to work safely with electrical systems, you probably should ask an expert before trying something specific.