Complex sentence: The Nubra river originating from the Siachen glacier also behaves like the Shyok, before Tirit the SE flowing river takes a NW turn on meeting the river Shyok.
Split into simpler sentences: The Nubra river, originating from the Siachen glacier, also behaves like the Shyok. Before Tirit the SE flowing river Nubra takes a NW turn on meeting the river Shyok.