What are some ways in which I can lower stress significantly in the next few weeks?

I am undergoing medical procedures in the next few weeks that require that I lower stress but I am under extreme stress from work and other conflictual situations (appeals to administrative decisions, dealing with disabilities and the bureaucracy around getting help which can be adversarial because the systems are designed around denying such help which cause a lot of anger). I have a history of severe trauma, the medicines I am taking make me extra sensitive to stress (jittery/on edge) - it has just been a lot of extreme stresses in the last 7 years and I am psychologically depleted and often considering not going on. The places that are supposed to help do not help which makes me even more hopeless.

When I am so on edge like this, it is hard to focus and meditate (and I do struggle with ADHD and anxiety which make it even harder).

Are there any techniques that can lower my stress level at least a bit?

I struggle with following long videos as my attention drifts but am able to read essays and (shorter) books.

Thanks for any help.