Studying Korean! How do you say these sentences?
I wanted to ask a bulk amount of sentences through which i can talk and communicate better. I can read however, I understand very less. What would you suggest be the best way to understand sentences faster? and how do you say these in Hangul? (no need for romanization)

- So much to do in so little time.
- Stop this public display of affection (as a joke)
- You should seriously stop.
- Is it just me or it's just really hot?
- There's so much going through my head.
- You grew up too fast. Slow down.
- I'll be supporting you no matter what.
- I recently bought a/an (item)
- How is it?
- I think i'm having a heart attack soon.
- I'm freezing to death.
- Too much to handle.
- His smile is brighter than my future.
- How do you handle to stay calm?
- Perhaps, is there any (item) here?
- Sorry for the misunderstanding.
- I'm here whenever you need a friend.

Sorry for a lot of questions and thank you!also, "I wish I could be ______"

Question

Studying Korean! How do you say these sentences?
I wanted to ask a bulk amount of sentences through which i can talk and communicate better. I can read however, I understand very less. What would you suggest be the best way to understand sentences faster? and how do you say these in Hangul? (no need for romanization)

- So much to do in so little time.
- Stop this public display of affection (as a joke)
- You should seriously stop.
- Is it just me or it's just really hot?
- There's so much going through my head.
- You grew up too fast. Slow down.
- I'll be supporting you no matter what.
- I recently bought a/an (item)
- How is it?
- I think i'm having a heart attack soon.
- I'm freezing to death.
- Too much to handle.
- His smile is brighter than my future.
- How do you handle to stay calm?
- Perhaps, is there any (item) here?
- Sorry for the misunderstanding.
- I'm here whenever you need a friend.

Sorry for a lot of questions and thank you!also, "I wish I could be ______"

Answer

- So much to do in so little time. 시간은 없는데 할 일은 이렇게 많네.
- Stop this public display of affection. 사람들 많은 데서 이렇게 (진한) 애정 표시 하지 마.
- You should seriously stop. 정말 그만둬 / 정말인데 그러지 마.
- Is it just me or it's just really hot? 내 느낌이 그런가, 이니면 정말 너무 더운 건가?
- There's so much going through my head. (내) 마음에 상념이 가득해 / 마음이 아주 복잡해.
- You grew up too fast. Slow down. 넌 너무 빨리 자란다. 속도 좀 줄여.
- I'll be supporting you no matter what. 무슨 일이 있어도 널 도울게.
- I recently bought a/an (item)  (난) 얼마 전에  을 하나 샀어.
- How is it?  (이건/그건) 어떄? / 어떤 거 같아?
- I think i'm having a heart attack soon. 곧 심장마비(가) 올 것 같아 / 곧 심장이 멈출 것 같아.
- I'm freezing to death. (나) 추워 죽겠다 / 이러다 동사하겠다. 
- Too much to handle.  할 게 너무 많네 / 손이 딸리네.
- His smile is brighter than my future. 그 사람 미소가 내 미래보다 밝아.
- How do you handle to stay calm? 어떻게 냉정을 유지하니?
- Perhaps, is there any (item) here? 혹시, 여기 (이) 있나요?
- Sorry for the misunderstanding. 오해해서 미안해요.
- I'm here whenever you need a friend. (네게) 친구가 필요할 땐 내가 항상 여기 있어.

- I wish I could be .  이 될 수 있으면 좋겠다 / <>가 된다면 얼마나 좋을까?