In this case the class teacher of your child is the first contact person. Parents, together with the school should consider which help can be offered, which measures are meaningful.
Individual support and additional support measures for learning difficulties are the central task of the schools in Thuringia (https://www.schulportal-thueringen.de/individuelle_foerderung/praevention_lernschwierigkeiten).
Support is also available from the School Psychology Service in Thüringen: https://www.thueringen.de/th2/tmbjs/bildung/einrichtungen/schulpsychologischer_dienst/
Pupils from families who get help for living can get benefits for learning support from the education and participation package (https://buerger.thueringen.de/portal/?SOURCE=PstView&PSTID=853253).