In Germany you can invest your money in various financial instruments through many online brokers available. There are banks that offer trading accounts as well. To start investing, you must have 2 important things that is a Broker and Depot Account
Broker- As the medium between the exchange and you, the brokerage institution acts as the intermediary.
Depot Account - A depository account is an institution where you place your financial instruments, like stocks, ETFs, or funds, for safekeeping. In German, it is called a Wertpapierdepotkonto.