My family

There are five people in my family: My family have 5 persons. My mum and my dad, my little brother, and my uncle, and I. [When ever you have a list of people in English it is considered polite to end with 'I', rather than start with 'me',] My mum is a teacher in a primary school in Santillana del Mar. In this village, you can visit the Altamira's cave. My father works in a factory in Santander, the capital of Cantabria in Spain. My brother, who is four years younger than me has 4 years left than me, and he works in a car shopof car. He has a girlfriend and she is my friend [alternatively 'we get on very well.'] . Now, my uncle is currently unemployed, but he is looking for work, making use of lots of courses. haven't a job but he has a lot of courses for search a job. And I, I'm now  At the moment I don't have a job, but I am studying hard to get a good job. haven't a job but I study for get a good job. I'm a teacher but I need to pass a exams of in English to be a teacher in a public school.

[This read very well, just a few corrections to help it sound more natural.]

My family

There are 5 people in my My family: have 5 persons. me, my mum and my dad, my little brother and my uncle. My mum is a teacher in a primary school in Santillana del Mar, In this the village where you can visit the famous Altamira's cave. My father works in a factory in Santander, the capital of Cantabria in Spain. My brother has is 4 years left older than me, and he works in a garage shop of car. He has a girlfriend and she is my friend. Now, My uncle haven't hasn't got a job now, but he has is taking a lot of courses to help in his for search for a job. And I, I'm now haven't a job now but I am studying for to get a good job. I'm a teacher but I need to pass an exams of English exam to be a teacher in a public school.

The parts in pink are not wrong, they are changes to make it sound more natural.

You can change to be a teacher to to teach or to work.

My family

In my family there are five - mum, dad, little brother, uncle and me of course! have 5 persons. My mum and my dad, my little brother and my uncle. My Mum is a teacher in a primary school in Santillana del Mar, a small In this village where you can visit the Altamira's cave. My father works in a factory in Santander, the capital of Cantabria in Spain. My brother has is four years younger left than me, and he works in a car-sales (?)shop of car. He has a girlfriend and she is who happens to be my friend. Now,  At the moment my uncle hasn't a job, but he has a lot of options for finding courses for search a job. And as for me, I'm now haven't a job either right now, but I am studying hoping to get a good job. I am a teacher but I need to pass a exams of some English exams to be qualify as a teacher in a public school.

My family

My family has 5 people: my mum, my dad, my little brother, my uncle, and me. My mum is a teacher in at a primary school in Santillana del Mar. In this village, you can visit the Altamira's cave. My father work in a factory in Santander, the capital of Cantabria in Spain. My brother is 4 years younger than me (to sound better you should use "than I am" and not "than me," but it's not a huge problem), and he works in a car shop. He has a girlfriend and she is my friend. Right now, my uncle doesn't have a job but he is taking a lot of courses to [help him] search for a job. And I...I don't have a job but I am studying to get a good job. I'm a teacher but I need to pass English exams to be a teacher in a public school.