after 2 days of application they sent me a mail for skype interview, they asked me to prepare a 45-minute presentation. During the skype interview, they told me that the presentation is very long,

Application on-line, then first technical phone interview, then on-site interviews including presentation of assignment. The decision is mainly made based on technical skills, the interview with HR is less important. I didn't do very well during first interview but still I was invited on-site.