I hope your father passes quickly and painlessly. I can't imagine how awful it'll be when my parents pass away, they're like my anchor in this world...
There is an answer to why there is so much suffering. That's the question us Jehovah's witnesses get all the time. https://www.jw.org/en/library/brochures/What-Is-the-Purpose-of-Life-How-Can-You-Find-It/Why-So-Much-Suffering-and-Injustice/
In short, it's because 1. Adam and Eve rebelled against God, causing them to get thrown out of the perfect paradise they lived in. Once they had children, their children continued the tradition of sin, probably not being taught any better by their parents. Sometimes I think "well we're not Adam and Eve, so what if we didn't sin once? Would we be set free basically?" but all humans except Jesus eventually sin, even before they knew what a sin is, and even Jesus had to suffer since the world is ruled by sin.
2. Our sinning in itself is causing the terrible situation in the world. Every time we act selfishly and hurt other people we're contributing to it, and 8 billion people constantly make decisions that hurt other people and have created systems that often rewards it. If you lie and cheat and you will get an edge in any work place. If someone hurts you, you're almost expected to hurt them back. And the cherry on top is that God couldn't allow us to live forever due to our sinning, meaning that we suffer health defects and die eventually, but in a world like this I'd argue that it's more of a blessing than a curse. Who would want to live forever in this kind of world? Instead, we get to pass away and hopefully if we did things right we'll get to enjoy paradise once we're resurrected and all evil is wiped out.
3. People are constantly influenced by the evil of demons nowadays. It used to be more explicit in the past (bible history), people could interact with them directly, they got possessed, could do some weak although real magic when they allowed them, and this stuff was evidence in itself for that they existed, although they most certainly believed that these were the act of their false gods. Nowadays, it's more insidious, working behind the shadows with only one end goal: cause suffering and make us all turn away from the true God so that they can win the debate whether humans will follow God from their own will or not.
Job is a good example of this https://www.jw.org/en/library/bible/study-bible/books/job/1/
As you probably know, he was a devout man that God loved the most during his time because he was the most righteous person. Satan hated this, and debated with God that Job was only worshiping God because he had a life free from suffering, which lead to Satan getting the opportunity to cause some real suffering to Job to get the chance to prove his point. Job didn't know who caused him to suffer was Satan, so he blamed Jehovah God. We're all living Job's narrative nowadays, having to prove to Satan that despite our suffering we choose to walk with God because we believe that he will free us from it one day and return us back to a paradise.
