I was always that introverted person in school from primary to high school,. I remember every holiday I was thinking about meeting new people (the) next year, but never did. I was always that introverted person in school from primary to high school. I remember every holiday I was thinking about meeting new people (the) next year, but never did.

Strictly speaking, "introvert" is a noun; the adjective would be "introverted". In casual conversation, however, "introvert person" would be understood and accepted.

I was always that introverted person in school, from primary to high school,. I remember that every holiday I was thinking about meeting new people next year, but I never did. I was always that introverted person in school, from primary to high school. I remember that every holiday I was thinking about meeting new people next year, but I never did.

Introvert = noun. "She's an introvert." Introverted = adjective. "She is introverted." Plus a couple of edits to improve the flow.

I think I didn't make friends, because I wasn't able to open a discussion or start a conversation,; I always waited for people to do so. I think I didn't make friends because I wasn't able to open a discussion or start a conversation; I always waited for people to do so.

I think removing the comma allows the sentence to flow better and more naturally.

I think I didn't make friends, because I wasn't able to open a discussion or start a conversation, I always waited for other people to do so. I think I didn't make friends because I wasn't able to open a discussion or start a conversation, I always waited for other people to do so.

First comma removed because you are directly explaining why.

This wasn't the only obstacle,; I think it's also because I had never felt confortable with someone,. I'm a very selective and sensitive person so I can't be around fake people. This wasn't the only obstacle; I think it's also because I had never felt confortable with someone. I'm a very selective and sensitive person so I can't be around fake people.

This wasn't themy only obstacle,; I think it's also because I (had) never felt conmfortable with someone,. I'm a very selective and sensitive person. I can't be around fake people. This wasn't my only obstacle; I think it's also because I (had) never felt comfortable with someone. I'm a very selective and sensitive person. I can't be around fake people.

The "had" is optional here, a bit better without it in my opinion

I've always dreamed of a soulmate, someone who understands me without talking, because I'm not that expressive of a person;. I've always dreamed of a soulmate, someone who understands me without talking, because I'm not that expressive of a person.

(1) "Always" implies a continuous period of time, rather than any specific moment. So, the past continuous tense "I have" is more appropriate. (2) "Someone" is singular, so "understands" is expected.

I always dreamed of having a soulmate, someone who could understand me without talkinghaving to speak, because I'm not that expressive of a person;. I always dreamed of having a soulmate, someone who could understand me without having to speak, because I'm not that expressive of a person.

I wanted a calm person who can keep my secrets, someone who never finds what I'm talksaying boring or with nosensensical, someone that weI can spend hours with without feeling bored. I wanted a calm person who can keep my secrets, someone who never finds what I'm saying boring or nosensensical, someone I can spend hours with without feeling bored.

(1) Again, "someone" is singular, so the "finds" is expected. (2) Alternatively, instead of "what I'm saying", you can also say "what I'm talking about". (3) "Nonsensical" is the adjectival form of "nonsense".

I wanted a calm person who canould keep my secrets, someone who would never find what I'm talking boring or with nonsenseical, someone that we canwho could spend hours with me without feeling bored. I wanted a calm person who could keep my secrets, someone who would never find what I'm talking boring or nonsensical, someone who could spend hours with me without feeling bored.

Speaking about possibilities / hypotheticals: "could" rather than "can." Also why we add "would" in this line

But now this isn't my dream anymore, and I see that it was good for me to not havinge friends at that age, because I still feel uncomfortable around people. But now this isn't my dream anymore, and I see that it was good for me to not have friends at that age, because I still feel uncomfortable around people.

But now this isn't my no longer a dream anymorof mine, and I can see that it was a good thing for me to not havinge friends at that age, because I still feel uncomfortable around people. But now this is no longer a dream of mine, and I can see that it was a good thing for me to not have friends at that age, because I still feel uncomfortable around people.

Re-worded the start to sound a bit more idiomatic