I am after getting kicked out of university for academic underperformance 3 years ago, going back in this autumn. Is there anything that I need to know?

My major is aerospace engineering. Covid-19 along with my past life style, depression from deaths of those close to me, a toxic and dangerous domestic environment, and my misguided way to life are what ultimately lead to me failing classes that I could have gotten an A in every single one and 100% in most. In these past 3 years, I battled and defeated a gaming addiction, got decent work to where I saved up all the money I need to go back, and have somewhat healed what might be a form of brain damage. I am autistic, but I have not had anything like this until nearly 2 years ago which I think stress, lack of sleep, dehydration, malnourishment, and possibly something from not brushing my teeth are the cause. Difficulty with creating things in my head, but have improved and have reversed some memory decline (my memory was and is still very good, but it used to be far better).

In all this time, I am largely unaware of what has been going on in academia. I have not stepped foot in any classroom in nearly 5 years. I got the bad grades entirely online. I do not know what has happened when all the classes went back to in person. I have heard about the usage of AI like Chat GPT. Are they something I ought to worry about or should consider using myself? Are there and social changes to the classroom like what a professor or student can say about their personal lives? Is it true that people are using AI to cheat so much that nearly no one can actually pass tests without the internet anymore? Is it true that people in university are not knowing how to read or do very basic things related to school? Are the standards lowered and/or lowered so much that teachers can’t even test them? Are the extracurricular activities still active? Are people in STEM still getting hired? I’ve heard that everyone, including those in STEM, are facing more challenges to getting hired. If so, what should I do as someone trying to become an engineer?