You should say:
– what decision it was
– what difficulties you faced
– how you made the decision
– and explain why it was a difficult decision.
It was when I prepared the application form for the university entrance exam that I had to make an important but difficult decision. At that time, I was at a crossroads, where I had to decide which university to apply for. Actually, my interest was in economics, which was taught in two separate universities, one of which specialized in international trade while the other focused more on the national economy.
Fortunately, my sister, who graduated from an economics college, gave me some sound advice. Having weighed up the pros and cons of each school, she encouraged me to choose the university specializing in international trade. Finally, I applied for this school after thinking carefully about all the options.
At present, I feel so satisfied with the learning environment of this university that I am always thankful for my decision as well as my sister’s advice. Without her guidance, I probably wouldn’t be as content with my university life as I am.
– at a crossroads: [expression] at an important point in someone’s life or development.
Example: His life was at a crossroads – whether to join the army or to continue studying at university.
– sound advice: [adjective and noun combination] sensible and reliable advice.
Example: My parents gave me sound advice about my choice of career.
– weighed up the pros and cons: [expression] considered carefully the advantages and disadvantages of something.
Example: Having weighed up the pros and cons, I decided that it would be more useful for me to learn English rather than French.
– learning environment: [noun phrase] the conditions that affect the behaviour and development of people who are learning a subject.
Example: The school had the latest technology, the buildings were modern and the teachers were very helpful – it was the perfect learning environment.