It's painful because my father is so stubborn...

Since my wife also uses this forum, I will delete the title and content later. I ask for your understanding.
My father has always had a strong sense of self, but it seems to be getting worse.
It would be too long to write everything, so I will only mention some shocking parts of a recent conversation.
1. When I said, 'When I have something to worry about in life, I ask people around me (people my father knows), like OOO or OOO, and if that doesn't solve it, I sometimes ask on anonymous message boards (actually, I'm talking about this place haha ^^), and lately, I even ask AI,' my father said:
'When I have worries, rather than asking others, I think about it deeply by myself. And as you said, even if you ask people around you, you're just asking people in their 40s who are similar in age to you. I don't think you can find an appropriate answer by talking among people who only have that much insight.'
So I countered by asking, 'Then, are you saying that because people in their 40s like me have short life experiences, our worries are meaningless, and I should ask people in their 70s or older like you?'
He replied, 'In my opinion, in those cases, it is better to read classics like the Analects. The answers lie in the classics written by great geniuses.' -_-
So I said, 'Sure, those books might have good content, but isn't it highly likely that they won't have answers to the specific and individual matters I am facing right now?'
I don't remember his exact response after that, but he seemed to brush it off vaguely.
Is my father's way of thinking appropriate? -_-
2. He says that just as Chung Ju-yung shared wisdom by having various conversations while eating breakfast with his sons every morning, he thinks it would be good for our family to gather and have a meal once every two months (including me, my sibling's family—8 people in total—and my parents). However, he mentioned that my mother opposes this.
I feel like this isn't a common way of thinking either, so what do you all think?
3. He still gives a lot of advice (which is actually interference) to me and my wife, who are in our mid-40s and have two children. For example, he advises us not to buy a house in Seoul because it's too expensive, but to move to a slightly less desirable neighborhood to reduce the jeonse deposit, and then use that money to invest in stocks or something else to grow our wealth.
There have been several times when I wanted to buy a house, but my parents always believe that 'Seoul house prices are excessive and will definitely fall' and 'It is not good to take out loans for excessive investment because you will struggle with interest.'
However, considering my age and the fact that I have a family, I believe that my wife and I should be the ones making the decisions. Even if our judgment is wrong and the result is bad, I see it as a learning process, but he still seems to have a strong desire to prevent me from failing. I wonder if everyone gives this kind of advice or if my father is just unusual.
4. A few days ago, he came to my house to watch the kids for half a day.
Because of my sleep health, I sleep separately from my wife. My wife tends to open the window slightly for ventilation after waking up in the morning, but only opens the curtains a little bit.
Since we are in a jeonse house, the curtains are in poor condition, making it difficult to open and close them frequently. Also, since our house faces south, it gets too hot during the day if the curtains are wide open, among other reasons.
However, the moment my father arrived at my house, the children were jumping around on the bed in my wife's room, and he told them, 'Kids, the room is too dark, so open the curtains.'
In that moment, I thought, 'This is my house, and specifically my wife's room; isn't it inappropriate to judge whether the room is bright or dark by his own standards and instruct them to open the curtains? Or is this a possible piece of advice and am I just being too sensitive?'
But as expected, while the children were opening the curtains, the rod came loose, and I had to exhaust myself fixing it.
Anyway, I am asking because I am now confused whether it is normal for a parent to come to their child's separate home and tell them to open the curtains because the room is dark.
There are many other things, but I will omit them as it would be endless. I am seeking answers to the points above.
Today, I am going to a bookstore to see if there are any books that might bring about even a little change if stubborn elderly people like my father read them. People say people don't change, but I don't 100% agree with that. I believe my wife and I have changed in some aspects.
My father and I will see each other for at most 20 years, or at least 5 years. While there are thankful and good memories, there have also been many negative memories due to this stubbornness, so I want to minimize them as much as possible. So, I plan to go to the bookstore, find a book that might change someone like my father, buy it, and try to initiate a change by writing a long letter.
Even if it's not effective, I feel like I should try so that I won't have any regrets...
It is true that I am grateful because much of the many strengths I have came from my parents, but it is also hard because there are quite a few frustrating aspects.