Understanding G1 Garbage collector

[Manavjeet Singh]

Greetings!
I am currently trying to understand the source code of the G1 garbage
collector in OpenJDK14. I learned the working of G1 from
https://www.oracle.com/technetwork/tutorials/tutorials-1876574.html. I have
also figured out the source code of G1 is present in
jdk14/src/hotspot/share/gc/g1/ folder.
Can someone please suggest where to dive into the code. I am trying to
locate the code related to young generation marking, collection and
evacuation phases.
Thanks and regards
Manavjeet Singh