I have just read part 1 in Naruto which went on for like 4.5 years or something, and there is no mention of Madara, they show his statue and talk about how that conflict was about the founding of the leaf but there is no other mention of him. Obito is mentioned two times, the first is the one above the second is like the last chapter.
Of course there is the moment where Itachi says there would be 3 ms users if Sasuke learned it as well.
There is a difference between first time mentioned and first time foreshadowed.
As i said madara was first mentioned in part II when Sasuke and Naruto talk with Kurama.
BUT he was foreshadowed in one of the sasuke´s flashbacks when they were talking about the third uchiha survivor. Later one when we still didnt know that the masked guy is obito it is said that he is obito thus the conclusion that the guy during the uchiha massacre was Madara.
First time obito was mentioned was the first few chapters
When kakashi told sasuke,sakura,and Naruto about the memorial where his friends name was written
He even passed them because "those who don't follow the rules are trash but those who don't care about their comrades are worse than trash"
And obito was first shown in chapter 16 titled 'who are you'