You can get help from the regional youth welfare offices and health offices.
An overview of Youth welfare center in Baden-Württemberg can be found here: https://www.kinderinfo.de/jugendaemter/baden-wuerttemberg/
Guide for people with disabilities in Baden-Württemberg: https://sozialministerium.baden-wuerttemberg.de/fileadmin/redaktion/m-sm/intern/downloads/Publikationen/Wegweiser-f-Menschen-mit-Behinderungen-BW_2016.pdf
Further information can be found on the website of the Federal Government's Disability Commissioner www.behindertenbeauftragte.de/DE/LS/Themen/KinderJugendlicheFamilien/Fruehfoerderung/Fruehfoerderung_node
Family Advisor: www.familienratgeber.de