Director of the firm is threatening to ruin my career

Director of the firm is threatening that if I take a leave, he will ruin my career.

TLDR: Due to some family commitments, I applied for a 4 day leave and my director rejected, I have to go bc it's really important and I conveyed the same to him. He said that if I take the leave, he will fire me and ensure that there are strong negative remarks citing that I'm an indisciplined employee ruining my future employability prospectus.

So I work in this startup and it's been close to a year. Due to certain reasons I was working from home in the month of November (this was discussed with the management and they granted the same). In December, due to certain reasons, I had to take two days due to medical reasons (we don't have a sick leave policy so I had to use my PLs).

This commitment is extremely important for my family and hence I need to be present, due to the job I have barely gotten the time to attend any family events bc of their work culture and their you-cannot-use-your-leaves-if-the-reason-is-not-serious.

After I applied for the leaves, I went ahead and spoke to my manager for the same to which she said she doesn't have any issue but the leaves are always approved by the director (I think this is micromanagement). I went ahead and then spoke to the director since I had to make reservations for the same and my director straight up rejected my request. I mentioned the reason in quite detail and to which the management mentioned that they will think about it.

A couple of days later, I went to meet the upper management for the same and the final decision was that they cannot sanction leaves bc I was wfh the entire November and I took a couple of days off in December (The leaves I'm asking here are the ones which one can take in a calendar year, I didn't ask for anything above what has been mentioned). I further mentioned that it's really important for me to be there and I will have to go to which my director mentioned that if I go, the management will fire me o