Have you seen the notebook feature here on italki?  Writing regular notebook entries will allow you to get ongoing feedback like Nick Dennis just gave you.  I looked at your profile and it does not look like you have tried that out yet.  If you write entries and articles and do not get corrections, you might book a lesson with a teacher. (I think it is a good idea to try different teachers.  If you try a few, you are likely to feel which one really seems to be able to teach you things that are useful.)

I also agree with Alex Nguyen about using some of the MOOCs like coursera.org and edx.org.  You can take the courses without credit without any cost.  I like to do this and then I only feel obligated to use the parts I like.  This one, for example, might be good for you

https://www.edx.org/course/how-write-essay-uc-berkeleyx-colwri2-1x-2 ; (If you take it not-for-credit you can see if you already know everything taught in the class or not.)

Here´s one that may be a bit more advanced  https://www.edx.org/course/english-grammar-style-uqx-write101x-6

Hi Priscila. Going by your last post , you're writing level is already at a very high level. There's just a handful of minor grammar errors or unusual sentence constructions that suggest you're not a native speaker. However, if you are a professional writer, then it's important that your writing is close to perfect, because that's what you are being paid to do.

It could take years of study to get your writing to that perfect level (writing is arguably the hardest of the language skills to master). But instead of delaying your dream of being a writer until you reach that level, I suggest in the meantime that you ask a native speaker to proof-read your articles before submission.

You also asked for feedback, so I will point out a couple of very small errors in your last post:

"I got some feedback" - "I received some feedback" reads better in a professional article. "Got" sounds too colloquial, better suited to spoken English
"...made me realize that I thought that my writing skills were okay; however, there is a lot to improve". It should read "...made me realize that although I thought that my writing skills were okay, there is a lot to improve".
"foreign people" - "foreigners" sounds better.
"...what I write express..." - should be "expresses"
"...taking all of this in consideration..." - should be "into" not "in"
"The funny part is: I work..." - you don't need the colon, or even a comma.
"...I never had issues" - should be "I've never had issues". (This is because the first part of the sentence is in present tense, so use the Present Perfect)
"...many people ask me to read" - should be "...many people suggested that I read" or "...many people advised me to read".
"Penguin" should be capitalised, as should "Style"
"...I am not sure I am going to the right direction still" - should be "...I am not sure if I'm heading in the right direction"
"At the end" should be "In the end"
"...a proper grammar" - delete "a"

When I wake up I write about how my day is going to be, about all things that I want to do.

before sleeping I write about what happened.

You can watch a movie or read a article and try to write an abstract.

Sometimes I just create an story to practice new words that I learned.

These are the ways I've been practicing.

Obs: Writing in ITalki has helped me a lot. People are usually very helpful with corrections.

Thank you @charlescuy! I work with Human Resources, and after a sabbatical period at home to take care of my little kids, I am trying to rejoin the market. I am using LinkedIn to do networking, so I am writing some articles over there and connecting with many people; however, I got some feedback that made me realize that I thought that my writing skills were okay; however, there is a lot to improve.

I've always worked with foreign people and reported to them. I've also lived and worked in US for some years; but all of this does not mean that what I write express what I want to mean. So, taking all of this in consideration, I understand that it is time to stop, re-think my priorities and improve what is necessary to ensure that I am able to do a good job. Moreover, I believe that if I am feeling that pain in the stomach - which I have never felt before, to be sincere with you - I fear what I am writing.

The funny part is: I work as translator while caring for family and I never had issues. Anyway, you might ask why I am telling this long story. The reason is that many people ask me to read - and I fully agree with them, because it is the same with Portuguese, for instance.

I love to read and I can spend hours doing it, but I am not sure what type of books would really help me to improve my writing skills. I have a penguin book at home, and I am searching the "Elements of style" from Williams Strunk locally to see if these type of books can help me; but I am not sure I am going to the right direction still.

At the end, I love English and I love to learn. I am intending to even learn Norwegian or French also. But, I want to communicate using correct words and a proper grammar. Do you guys know if I can post here the article that I wrote, so perhaps people could fix it? It is published already, so people could give me their feedback and I could see how I can improve in some way. Is it possible at italk?