i want to ask ,are the uygur and the yugur in china are the same ethnic,some sources say yugur was the dialect of uygur ,is this true ,thank you .

I have never heard of "Yugur".. is it a sub-ethnicity of Uygur?

Yugur and Uyghur are seemingly related, but they are different ethnicity in China.
In Simplified Chinese, Uyghur is "维吾尔族" while Yugur is "裕固族".
East Yugur speak a Mongolic language whereas West Yugur spoke a Turkic language (as Uyghur).

both practises islam right?

No, the Yugur are generally Buddhists. There is very little similarities between the Yugurs and Uighurs other than that they both speak a Turkic language and claim to have similar origins. However culturally and racially, they are significantly different.