改grammer, 最好改formal d, part 1

Your writing is good, it just needs a little touch-up to be perfect.

I am a university undergraduate. Like other full-time students, I like shopping, making my own lunch and dinner with friends, singing karaoke, buying clothes, CDs and video games. My income comes mainly from my family and my part-time jobs. Therefore, I cannot afford something very expensive. I usually spend $500-1000 on F&B each month.
No need to put "the" before other full-time students, since you are referring to full-time students in general, and not to a particular group of students.

I like to shopping wrong

You can't use ING after "TO", "TO" is always followed by a bare inifinitive, except in exceptions like "I look forward to seeing...."

enjoying karaoke wrong

We usually say "singing karaoke", or "enjoy singing karaoke".

My income is mainly from chinglish

Should be: my income comes mainly from...

Just to clarify, what does F & B stand for? Food and Boarding or Food and Beverage, or something else? Better use the exact words other than these ambiguous abbreviations, since you want it to be formal, and as a rule we don't use abbreviations in formal writing.

I am an undergraduate univerity student who, like many other full-time students, enjoys shopping, having lunch and dinner with friends, and karaoke. Whenever I go shopping I buy clothes, CDs and games. My income comes mainly from my family and the salaries I earn from part-time jobs. Hence I am unable to afford anything expensive. I usually spend about $500-1000 on F&B every month.

I am a University undergraduate , like many other full-time students, I like shopping and making lunch and dinner with friends. I also enjoy karaoke, buying clothes, CDs and games. My income is mainly from my family and part-time jobs. Therefore, I cannot afford anything expensive. I usually spend $500-1000 on F&B each month.

Remark:
when there are a list of examples, try sorting them and separating them into shorter 'segments', like
i love basketball, swimming, reading, singing ...
-->>I love basketabll and swimming. I also enjoy reading and singing...

I am an undergraduate University student, like the other full-time students, I like doing shopping, making lunch and dinner with friends, enjoying karaoke, buying clothes, CDs and games. My income is mainly from family and part-time jobs. Therefore, I cannot afford something very expensive. I usually spend $500-1000 on F&B (the magazine "Fashion & Beauty) each month.

I am an undergraduate student. Like most of the full time students, I like to shop, karaoke and have lunch and dinner with friends. The main sources of my income are allowance from my family and salary from my part-time jobs, therefore, I cannot afford to buy expensive things. I usually spend $500 to $1000 on F&B each

I am an undergraduate student. My hobbies like the other full-time students, for example shopping, karaoke, playing TV games, listening the music, making lunch and dinner with my friends. Most of my income is from my part-time jobs, so I cannot spend too much to buy the expensive things.Usually I only spend $500-1000 on F&B each month.