Answer:
External Conflict
Step-by-step explanation:
The uncle is the main source of the conflict, telling the main character that he should not believe in his abilities and that he has no right to believe he will accomplish anything. This, at some point later in the book, could cause internal conflict. However, at the moment of the uncle telling the main character he can't do anything, he is directly influencing the character from the outside. Therefore, it is external conflict.