The key teachings that should be understood and followed are 'The four noble truths' and 'The eightfold path'.
They had to give up everything including their clothes
they had to observe celibacy(look up the dictionary)
Theraveda is a sect that follows strict Buddhist teachings.
Lord Buddha
Buddhist is all about the rice and ping pong in the ching chong with ur ding dongs, but Hindu is all about Tilak Patel's teachings and way of Curry.
A person is a Buddhist if he says he is a Buddhist. Someone who tries to follow the teachings of the Buddha is the kind of person who would call himself a Buddhist.
A tipitaka contains most of the Buddhist teachings.
Buddhist statutes are not used for worship. They are used to being to mind the teachings of the Buddha or his and his disciples actions. We bow to the Buddha in reverence to his teachings just as we bow to all beings.
Prince Shotoku helped spread Buddhism in Japan by building a grand Buddhist temple and by writing commentaries on Buddhist teachings.
That all phenomena arise from causes.
Prince Shotoku
Not sure what you mean by 'they' but the concept of 'holy' is a deeply personal thing in Buddhism, not proscribed strongly by any dogma. The essence of all Buddhist teachings sit withing the Buddha's Four Noble Truths. For some Buddhists the image of the Buddha is very important for others the teachings are 'holy' and for others the direct experience of these teachings might be seen as the foundation of the Buddhist path.
Buddhist belive in Lord Buddha, Dhamma ( his teachings), honorables Monks who followed teachings and attain nibbana.
It is fairly simple. If you have investigated the Buddha's teachings and have come to believe that this is the path (and it is a path) that you want to follow in your life then you simply need to take the refuge ceremony, either by yourself, or in a Buddhist Temple or with a Buddhist Monk. The refuge ceremony is your statement that you intend to use the Buddha (the first know enlightened one), his teachings (the Dharma) and his followers (The Sangha, which is the Monks, Nuns, lay persons that follow The Buddha and all enlightened beings (other Buddhas)) as your guides in life. It is well explained here: See : Related links