Hello,
You have the right to request asylum when in Germany. As far as I know, there is not a specific application one can make for subsidiary protection. A person makes an application for asylum (in German 'Asylantrag'). Then the asylum procedure decides what, if any, kind of protection status is to be given to the person. Subsidary protection is one form of protection that can be given as the result of an asylum application.
At certain airports in Germany, including Frankfurt, there is a special asylum procedure for a specific group of people who make an application for asylum. This is called the airport procedure (Flughafenverfahren) and is only for the following people:
Those from a list of countries Germany considers to be safe third countries of origin:
- Albania,
- Bosnia and Herzegovina,
- Ghana,
- Kosovo,
- North Macedonia,
- Montenegro,
- Senegal, and
- Serbia.
Those who do not have a valid passport.
For other people who apply for asylum, the regular asylum procedure applies.
Here is more information about the special airport procedure:
https://***.bamf.de/EN/Themen/AsylFluechtlingsschutz/Sonderverfahren/Flughafenverfahren/flughafenverfahren-node.html
This NGO works with refugees and asylum seekers at the airport:
https://***-diakonie--frankfurt--offenbach-de.translate.goog/ich-suche-hilfe/fluechtlinge/kirchlicher-fluechtlingsdienst-am-flughafen/?_x_tr_sl=de&_x_tr_tl=en&_x_tr_hl=en&_x_tr_pto=wapp