In my college there a discipline about linear algebra, i pretend to apply, but I don't know if I have the necessary know.
What is necessary to know to don't have difficult?
There some path or sequence to learning?
like first matrix, second complex numbers...
Linear algebra deals with linear spaces and certain properties and objects related to those spaces, especially around linear transformations, Matrices, inner producs and such...
It all begins with the definition of a linear space - a Vector Space. If you'll enter the course with some understanding of the definition and know what is a vector space basis, linear depended and what is a linear transformation and see some simple examples ($\mathbb{R^2},\mathbb{R^3}$) you'll already have most of the important concepts under your scope.
My advice - take a look what book is used in the course, or look for some good book (you can find tons of recommendations online. it is not super-important which book you choose, just pick one that was written recently and people of knowledge can recommend). Make sure you solve some of the problems in the book. You don't need to solve everything, you don't even need write a formal proof when solving. You just need to understand the ideas how to solve mathematical problems whithin linear algebra. If you do that you'll come in a very good shape to handle the course.
Linear Algebra is not only one of the most important in science and technology, but also a beautiful and intuitive theory. Good Luck with your studies!