The first step towards your new job is the job interview. However, you will only be invited if your application documents are convincing. The cover letter plays a crucial role: Because unlike in your tabular curriculum vitae, it is here where you present yourself as a personality - with your specialist knowledge, your experience and your motivation for the advertised position.
But also the structure, style and form of your application are decisive for the first impression: are the documents complete, carefully prepared and written correctly? Remember that your approach to your application will be viewed as a good representation of your work ethique! Please don't forget one thing: Nowadays, digital application via email is not only permissible, but self-evident.