No. Taekwondo and Kung Fu are both martial arts, but they are very different from each other.
Taekwondo is a Korean martial art with a strong Japanese influence. Kung Fu is a name used to refer to Chinese martial arts, a better name for which is Wushu.
Taekwondo is visually very distinct from Kung Fu, with a more rigid, linear form. The practice exercises used in Taekwondo are completely different to those of any style of Chinese martial arts; the clothing is different; the grade system is different; the traditions are different.
However, it should be noted that Taekwondo and a few styles of Chinese martial arts are thought to be genealogically related. Taekwondo takes a lot of inspiration from Japanese Karate, which in turn is inspired by styles of martial arts practised in south-east China. However, this is a very distant connection.