Now I have to use the key
F1 to get the pdf output.
I want to type the code of LaTeX and TeXMaker compile autonomously for me to see the output.
How to do that?
switching a comment to an answer
Thats a function that you probably do not want: it needs some time to render an average pdf document, so it makes perfect sense to do this only if the user wants it. Rendering the pdf on every keystroke or every n Seconds would result in quite heavy disk activity and CPU load. The solution is to get used to editing the source code. A good formatting of the .tex file can help (newlines, indentation, comments...). This question has some other suggestions: Live tex compilation