Not wanting to disclose PWD status but being asked during job applications

I believe similar questions have been asked here in the past but I wanted to confirm something a bit more specific, but this is still just a hypothetical question.

The law states it's illegal for employers to discriminate against PWDs, but I definitely know that it still happens because I've experienced it multiple times. For that reason, I never want to disclose my status to any employer any longer.

However, some do straight up ask, often in writing, if there are any medical conditions that would possibly hinder my work. I believe that it is not legally mandatory to disclose status (please correct me if I'm wrong on this; I am not able to see any clause that specifically states this but I believe it's implied by the anti-discrimination provision), however I acknowledge that my disability would sometimes affect my work. I would inevitably have flare ups that would cause me to be out sick more than an able bodied employee.

I still firmly believe I have the right to work, and 99% it is not an issue. But I was wondering what would happen if I answer "no" to the medical condition question and my disability eventually comes up when I ask for reasonable accommodation such as schedule adjustments, medical leaves, etc. Can employers reject the request on the basis that it was not disclosed to them beforehand, or can they straight up fire me if for lying in the application form?