If you live in Germany and have a Lenco TV with only DVB-T, then unfortunately you cannot watch digital TV. Your TV must have a DVB-T2 tuner in Germany to watch digital TV. However, it is not necessary to buy a new TV in that case, you can also purchase a separate DVB-T2 tuner. You connect this box to the HDMI input of your TV.
The box then transmits the digital signals to your TV.