How best to explain to a 7 year old
1. Why did God create that forbidden tree in the first place
2. Prophets and Imams always do the right things and don’t make sins, why did Prophet Adam listen to Shaitan and not Allah?

1- He created it to show us that life is a trial and we should be careful

2- Prophets and Imams don’t commit sins. What Adam did was not a sin, but he was rather deceives by Satan because Satan took an oath in God’s name that he was saying the truth, and Adam didn’t think he would lie while swearing in God’s name. Now all this happened to show us the consequences of listening to the devil so we become extra cautious and resist his evil whispers.