Burning incense for ancestors in traditional festivals is equivalent to believing in Buddhism?

In China, it is very difficult to really distinguish Confucianism, Buddhism and Taoism, including some folk traditions.

Incense to ancestors is generally a sign of filial piety. Of course, in Buddhism, believers should first respect filial piety.

Let's just say that to believe in Buddhism is to respect filial piety. You don't necessarily believe in Buddhism, but you generally believe in Buddhism, hehe

Maybe you can search for "Introduction to Buddhism for Beginners" in Baidu Library to have a deeper understanding of Buddhism.