One possible plot could be that Black Widow, seeing Peter's potential and also his need for a more stable family situation after the death of his uncle, decides to take him under her wing. She could train him in more stealthy and psychological aspects of being a hero, different from what he learns from Tony Stark. For example, she might teach him how to extract information from enemies without using brute force.
The plot could revolve around Black Widow adopting Peter after a major event. She realizes that Peter is too young to be on his own in the superhero world. So, she becomes his legal guardian. This would lead to some interesting dynamics as Peter has to adjust to living with Black Widow. She would introduce him to her network of contacts, and together they could take on new threats in the city, with Peter learning new skills from her every day.
A practical answer is Chapter 61, because it turns the idea into a concrete scene. The chapter opens with Hahahaha, oh my god, Jiang Li's mouth is even more venomous., adds pressure through The man's expression darkened for a moment., and ends on A cold shower is pretty normal, right?.
If you want the clearest chapter reference, go to Chapter 89. Early on, Director Sun took a step back, "What's the rush?; later, the chapter leans on It's true about the go-kart costing one point, but this time we're using....
If you want the clearest chapter reference, go to Chapter 80. Early on, Jiang Yan and Wen Jiaojiao, one so smug he was almost ascending to the...; later, the chapter leans on And this was exactly the scene Director Sun wanted to see..
Chapter 87 is the strongest chapter-level answer because it starts from Luckily, at that time, Jiang Li had already taken her pot of stinky... and follows through on I'm driven crazy by him every day.] [+1 from above!.
If you want the clearest chapter reference, go to Chapter 78. Early on, He Yun, too, tidied up and walked over to rest in the shade of a tree.; later, the chapter leans on After more than an hour of basking in the sun, his cheeks were....
The best chapter pointer here is Chapter 127, "He's Not Snobbish, Just Simply Bad-Tempered". It opens with Witnessing Jiang Li leave with a bucket, Jiang Yan refused to admit... and closes on He Yun, who chose the codonopsis, became the one with the most challenging....
If you want the clearest chapter reference, go to Chapter 120. Early on, Facing the sudden and somewhat strange request from Jiang Li, Director Sun...; later, the chapter leans on But, as if by some mysterious force, he still instructed his assistant to....
The best chapter pointer here is Chapter 93, "Why Consult a Fortune Teller When a Child is Lost?". It opens with Jiang Li looked back and saw several aunties linking arms, walking up the... and closes on I did the same when I was young, and when my dad found me, I got a beating....
If you want the clearest chapter reference, go to Chapter 78. Early on, He Yun, too, tidied up and walked over to rest in the shade of a tree.; later, the chapter leans on After more than an hour of basking in the sun, his cheeks were....
If you want the clearest chapter reference, go to Chapter 96. Early on, Jiang Li's words seemed absurd, yet there also seemed to be a trace of...; later, the chapter leans on Her hand holding the phone began to tremble uncontrollably..