This panel looks original to the house, 50 to 60 years old. There are other issues in here (mixed breaker brands, breakers that aren’t fully seated, service neutral and ground under the same lug, etc.) but I haven’t seen this type of ITE panel before. To access the breakers, it was a two part removal - the panel that hold the door, then a second dead front that sits in front of the breakers.
It makes sense that the mains feed the top set of breakers and the lower two sections are fed off the top set. Is this still a 200 amp panel like the label says?
Thanks for the help!