oh well - sorry, i am not professionell in that! 
#renew_before_expiry = 30 days
version = 1.5.0
archive_dir = /etc/letsencrypt/archive/server.kaifu-gymnasium.de
cert = /etc/letsencrypt/live/server.kaifu-gymnasium.de/cert.pem
privkey = /etc/letsencrypt/live/server.kaifu-gymnasium.de/privkey.pem
chain = /etc/letsencrypt/live/server.kaifu-gymnasium.de/chain.pem
fullchain = /etc/letsencrypt/live/server.kaifu-gymnasium.de/fullchain.pem
#Options used in the renewal process
[renewalparams]
account = e1d020d3ac2dc7058a077fd3dbd87f2d
authenticator = webroot
server = https://acme-v02.api.letsencrypt.org/directory