Great going on your first entry^^

Your note is mostly correct ^__^

Hi, my name is Silvia Camargo. I'm Brazilian. I'm finishing about to finish
high school and getting ready to enter the journalism
school at by the end of the year. I love music, books, films
and * series. I love fashion, hanging out with my friends
and all animals, especially my three dogs. Here in
Italki want to meet new people from different cultures and
improve my English.

You must understand that despite not having any gramatical inconsistencies some of your sentences would sound a bit odd to any native speaker. So, I suggest that you may modify your note like this --->

Hi I'm Silvia Camargo from Brazil. I'm about to graduate from
high school and getting ready to enter school of journalism 
studies by the end of the year. I love music, books, movies, fashion
and TV. I like hanging out with my friends. I have 3 dogs and I like to walk them around. Here in Italki, I wish to meet new people from different cultures and 
improve my English.

NOTE

*you dont HANG OUT with dogs

*try not to write many small sentences, instead join them suitably to make a more complete sentence.

*you use "AT" when refering to a place...like (at the station, at home etc)... but when you indicate time, generally "BY" is used...like (I'll complete this by next week...What is the time by your watch?)

*There is a subtle (small) difference between WANT and WISH... when you say you WANT something it (more likely) means that you WANT it immediately as in you are asking for something (...like in a shop you can say "I want 2 pounds of bread..."). In the context of this note WISH is more appropriate...( I wish to meet new people... I wish for a cup of coffee...etc)

First notebook entry: Introducing myself

Hi, I am Silvia Camargo from Brazil. I'm finishing off 
high school and getting ready to do journalism in
a school at the end of the year. I love music, books, films, fashion, hanging out with my friends and all animals, especially my three dogs.i would like to have a chat with new people,sharing their culture as well as to improve my english skills.

First notebook entry: Introducing myself

Hi, my name is Silvia Camargo. I'm Brazilian. I'm about to finish high school and getting ready to enter journalism school by the end of the year. I love music, books and films. I love fashion and hanging out with my friends. I would like to have a chat with new people, sharing their culture as well as to improve my english skills.

First notebook entry: Introducing myself

Hi, my name is Silvia Camargo. I'm Brazilian. I'm about to finish high school and getting ready to enter journalism school by the end of the year. I love music, books and films. I love fashion, hanging out with my friends and all animals, especially my three dogs. I would like to have a chat with new people, sharing their culture as well as to improve my english skills.

First notebook entry: Introducing myself

Hi, my name is Silvia Camargo, I'm Brazilian. I'm finishing
high school and getting ready to enter the journalism
school at the end of the year. I love music, books, films
and series. I love fashion, hanging out with my friends
and all animals, especially my three dogs. I would like to have a chat with new people, sharing their culture as well as to improve my english skills.