Dealing with stress

This is ok. However, main titles usually have capital letters for most of their words, e.g. Dealing With Stress - or - Dealing with Stress. It is up to you, though. It's a style matter, really.

As a 27 years unmarried working woman, I am dealing with a lot of stress everyday.

If you say, "As a 27-years unmarried working woman" you could be meaning that you have been an unmarried working woman for 27 years. However, perhaps you mean that you are aged 27 years. If so, you could say for example, "As a 27-year-old unmarried working woman".

A note about "everyday"
If you mean that you suffer stress each day, then the usual form is to write "every day" as two separate words, just as you write "each day" as two separate words. Here, you are using "every day" as a time phrase: it is an adverb. I think that this is what you are meaning here. However, the joined-up form, "everyday", is an adjective. It is used to describe something as ordinary, common, routine, the usual, etc. For example, "Fighting fires and rescuing people was just an everyday job for him" - and - "Living in poverty is an everyday fact of life for the people of that country".

A note about "a lot"
The phrase "a lot" is used commonly and serves the English language well on an everyday (!!) basis. However, there are alternatives that could be used for variety, for example - much; a great amount of.

At my workplace, I am in charge of one big project that provide thes 30% of the turnover of the society I work for.

It's a big responsaibility for me.

responsibility

Because whenever an issue comes to this project, it is my call to give a solution.

It is quite common in informal English to begin a sentence with "because", especially in speech. It is, however, grammatically incorrect! This is because "because" is a joining word usually better placed within the same sentence that prompts its use. So, you could join the above sentence, and this one here like this: "It's a big responsibility for me because whenever an issue comes to this project, it is my call to give a solution." I think this helps your text to flow a bit better.

And make the project work properly.

Following on from what I've said above, "and" is also a joining word, and it could be used within the same sentence, thus avoiding unnecessary breaking up of the text flow. So, "It's a big responsibility for me because whenever an issue comes to this project, it is my call to give a solution and make the project work."

Like every grown -up person, I have to clean and to keep the house tidy.

Like every grown-up person, I have to clean and keep the house tidy.

MakeFetch groceries every week.

Thinking about what I've said above, try to connect this sentence with the one above and the one below, without the use of full stops (periods). For example: "Like every grown-up person, I have to clean and keep the house tidy, fetch groceries every week and prepare meals on a daily basis."

Prepare meal fors on a daily basis.

as above

I anticipate everydayach day as much as possible.

I anticipate each day as much as possible.

So that when some unexpected problems happen at least I am mentally prepared.

You could join up the sentence above with this one, for example: "I anticipate each day as much as possible, so that when some unexpected problem happens, at least I'm mentally prepared."

As a 27 years old unmarried working woman, I am dealing with a lot of stress everyday.

At my workplace, I am in charge of one big project that provide thes 30% of turnover of the societcompany I work for.

Does turnover refer to loss of employees? Or profit? Turnover generally refers to the number of people that leave the company.

It's a big responsaibility for me.

Because whenever there is an issue comes toin this project, it is my call to giveI have to find a solution.

Added to thatIn addition, I have to take care of the house where I live.

Like every grown up person, I have to clean and to keep the house tidy.

MakI have to buy the groceries every week.

Prepare meal fors on a daily basis.

To deal with all the stresses, I have to be well organized.

I anticipateplan ahead everyday day as much as possible.