How can I prove I don't support my former religion to the gestapo?

As a former Muslim my faith for this religion was gone a long time. I never was even interested in it to begin with. I inherited the religion from my family because I love in a Muslim majority country. I don't have any hope for my country anymore because it's turning towards fanatism day by day. Those fanatists are torturing people who are not following Islam properly, burning books and telling horrendous things about women to the general public. I want to get out of this. I want to join FFL to fight for the right side of history for once in my life and save my sister before those extremists take over the country. But I don't know how can I convince the gestapo that I don't follow Islam. I can give them my social media accounts but there isn't much in them because I haven't posted anything for a long time. I am not interested in joining other religions because I have no faith in any of them and there's a big chance I will get caught lying. So is there anything else I can do?