I have already got the subject of what i wanted to write

[Gerald]

Dear Friend,

Please help me with this sentence below:

1.I have already got the subject of what i wanted to write (Should it be subjects?).

2.I never knew you are related to him. (can it be know instead of knew?).

3.What time should i come? (this sentence is correct?).

Gerald

[Esl_Expert]

Hello Gerald,

Here are my suggestions:

1.I have already got the subject of what I am going to write about.
(You can use "subjects" if you plan to write about more than one subject.)

2.I never knew you were related to him.
No, it does not make any sense to use "know" in this context.

3.What time should I come?

[Torsten]

I would also put a space after the numeration:
1. I have...
2. I never...
3. What time...
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