Apache Solr Extraction provides a means for extracting and indexing content contained in “rich” documents, such as Microsoft Word, Adobe PDF, etc. (Each name is a trademark of their respective owners) This module uses Apache Tika to extract content and metadata from the files, which can then be indexed. For more information, see https://solr.apache.org/guide/solr/latest/indexing-guide/indexing-with-tika.html
You will need Solr up and running. Then, simply add the extraction JAR file, plus the Tika dependencies (in the ./lib folder) to your Solr Home lib directory. See https://solr.apache.org/guide/solr/latest/indexing-guide/indexing-with-tika.html for more details on hooking it in and configuring.