You'll need to change some Variables in the Main.tex to fit your needs. Those Variables beeing your Name, date etc.
If you want to change the Picture or in generell the Appearance of the titlepage, you need to navigate to /inlcude/titlepage.tex and do so there. (Have fun and send me your coolest Title Page)
The different Topics, like "Einführung", "Durchführung" etc. will be edited in the tex files in the Folder a_content.
Have Fun, Your Captain Joni