- 백화점에서 산 양복 = A (ready made) suit I bought at the department store.
- 백화점에세 맞춘 양복 = A suit I got tailor made at the department store.
They are both correct but have different meanings. At 백화점, 산 양복 is more common nowadays.
* "제 부모님은 항상 저랑 제 동생을 맞춰요" - grammatically fine but a little unclear.
My guess is you meant "My parents always try to treat me and my younger brother/sister equally".
If that's the intended meaning, we would probably say it more specifically:
제 부모님은 항상 저랑 제 동생을 똑같이 대하려고 하셔요 [공평하게 대하려고 하셔요].
* Both 서류를 내세요 and 서류를 넣으세요 are fine for "submit" or "turn in".
- 서류를 내세요: 내다 is to submit to some organization/person.
- 서류를 넣으세요: 넣다 means to turn in. 내다 is more common traditionally than 넣다.
* 사람을 넣다, 계산에 넣다, 판로를 뚫다.
- 새로 연 매장에 사람을 넣어야 해[투입해야 해]. (투입하다 is much more common)
=> We must staff [assign personnel to] the newly opened store/showroom.
- 신기술의 평가할 때는 환경 영향도 계산에 넣어야 한다.
=> When evaluating a new technology, its effect on the environment should be considered too.
- 회사는 아프리카의 신흥 시장에 판로를 뚫었다.
=> The company penetrated into [developed a sales channel in] the new emerging markets in Africa.