"For a bigger company, for better conditions, for my personal growth, etc."

Why do we write resumes and self-introduction letters? To get the chance for an interview.
So, what should you do?
You should focus on how your strengths and skills can help the company achieve its goals.
A company is not a charity organization. The purpose of a company is to generate profit.
It does not exist because of your personal reasons.

"Born in a certain year, in a certain town, loved by a strict father and a caring mother, my father does this and that..."

This is how most self-introduction letters begin.
A brief introduction about your background is fine, but if you write half a page about it, it becomes an issue.
Let me be clear: HR managers are not particularly interested in where you were born or who your parents are.
The company¡¯s focus is on whether you are a good fit for the company, and whether you have the relevant experience and skills.
Describe the key roles you took on as you developed your career.

"I cannot claim to be an expert in my field."
"I cannot always implement everything I have learned in society, but I am trying my best to practice as much as I can."

Statements like these are often seen as humble.
While humility may be appreciated in other areas, it is never necessary in a resume.
When competing against hundreds of others, simply showcasing your strengths may not be enough, and humility can be perceived as a weakness.
Be proactive, confident, and make sure to highlight your strengths clearly.

For the first example:
"PDP stands for Plasma Display Panel, which is used in large TVs..."

This sentence has two issues:
First, in the U.S. and the UK, people refer to LCD TVs simply as LCDs, while PDPs are referred to as Plasma TVs unlike in Korea.
Second, there may be no need to explain what PDP is, as it could undervalue the reader's knowledge.
Do not include such explanations.

For the second example:
"If I had to compare my personality to an animal, I would be a bear?gentle yet firm and determined to achieve my goals. That bear is me."
"I am like OO?like the sea, water, forest, white, etc."

Such metaphors are not appropriate. The perception of animals and objects may differ between Korea and other countries. Additionally, HR managers may have different personal views.
In the U.S., bears are seen as dangerous animals, far removed from the qualities of gentleness.

In self-introduction letters, discussions about religion often appear, but it is not advisable to mention religion.
Although I have my own religious beliefs, recent statistics in Korea show that 46.9% of the population is non-religious,
18.3% are for Christian, 22.8% for Buddhist, and 10.9% for Catholic.
There is a high probability that the HR manager may be non-religious or follow a different religion, which could lead to potential bias.

"I will work harder on my English since I am lacking in it."

Many applicants tend to say they will work hard.
In books about American resumes, you will never find the phrase "I will work hard."
It is an obvious statement, and without any supporting evidence, saying you will work hard is ineffective.

Additionally, stating that you are not good at English is not advisable.
It would be better to rephrase the example like this:

Occasionally, I receive inquiries about ghostwriting, and it makes me question whether the applicant truly wants to get the job.
If you ask a stranger to write it for you, what kind of introduction will they provide?
They might write something generic, full of nice words or abstract statements.

However, what really matters are your unique personal qualities, skills, achievements, qualifications, and "specs" that the company wants to see.