Hello! Thanks for correcting me. If you don't mind I ask my questions based on your reply. I can find out my questions' answers by search but i will learn better when someone replied them 🫠
1) On the first part;
• You said they conflicted, but you erased both. Why "mostly", too?
• I said "their", I think it's plural so I used "-s". Am I wrong?
2) Second one
• What's the difference between good way and positive in this sentence? they sound same
• I hate using either and neither, it's hard to understand and using in sentences. So I'm trying to stay away with them. Is there any trick about that?
3) Third one
• Why can't I use " will"? I mean it's not happened, isn't it? According to structure of future tense; I can, you know.
• In addition, as soon as i know, "immediately" and "directly" have same meaning, haven't they?
8) "Also" and "at the same time" both are synonym, aren't they? What's difference?
9) To be honest, I knew that will be exactly wrong when i was sending my text. Because i always confuse the conditionals. Which condition is that? and what was its structure? Also, i had to use the word "amusing".
10) Why did you use " would"?
11) I would like to corrected with same word. Is there any way to make this sentence with "bizarre"?

Hello!

1) I removed "mostly" because I replaced the word "Everyone" with "most people" and saying "most" twice is redundant. I also thought this would be more accurate and concise to express the idea that people usually pick between the two colors according to gender. If, by using the word "mostly", you wanted to convey that people consider additional factors but mostly rely on gender, another word like "primarily" might sound smoother.

You are correct in that it's plural and "-s" can be used.
"Gender" sounds more natural because each person is assumed to only have one gender (based on the scope of the context). "Genders" sounds a bit more academic, and often emphasizes that different people in the group have different genders (or implies that a person in the group could have multiple genders). This could be relevant if, for example, you are talking about the distribution of genders across a group of people. This sort of distinction can sound clinical and is usually not necessary in casual speech.
"The people picked based on their eye colour."
"The students ate their lunch." "The students ate their lunches."

2) I changed "good way" because it sounds a little less native or natural in this specific sentence. "Good way" is grammatically correct. They differ in that "good way" is a bit more vague, while "positively" would focus more on peoples' evaluation or judgment.

"Neither" starts with "n" like other Negative words such as "no", "not", and "never". That's how I remembered it while learning English. Maybe you already know that though. I don't have any better tips :(

3) "Will" is correct. I removed it because "they immediately think" conveys more of a generalization (such as a social observation), but "will" emphasizes inevitability in this specific situation, so maybe it's better for this context and your intended meaning. I probably should have left it. Sorry for any confusion.

"Immediately" focuses on time. People will think about his sexual orientation right away, with no delay.
"Directly" focuses on manner or focus. People will think about his sexual orientation as the main consideration, without detours or distractions.
I thought "immediately" matched the intended nuance of the sentence better. If "directly" was what you meant, the way you used it is correct.

8) "Also" usually adds something in agreement or in addition. I changed it because the two sentences seem to have a partial contradiction. A colour is just a colour, but you also believe in their power.

9) 10)
The sentence "If everyone wears colourful clothes, they will have more amusing lives for sure" is not grammatically incorrect. I changed it to the "if ... would" second conditional because it seems unlikely that everyone will wear colourful clothes in the future. I changed "would" in the following sentence to match the previous sentence, because it was still talking about the same hypothetical scenario.

Haha, "amusing" is a good word. It conveys a lot.

11) You can just leave "bizarre". I only changed it because it seemed a bit strong.

I hope this helps.

*should say "people's" and not " peoples' "