Quick answer: Take the forest road toward Pangzhen, find it shut, then cross the Crimson Forest to the Village of Lu. The first Crimson Forest bell and the Illusion of Inanis scene come early on the way.
All objectives in Snake’s Reflection
The chapter has three objectives. They appear in this order, and each one sets up the next.
Crimson Forest first steps: the Crane Bell and Illusion of Inanis
The first bell in the Crimson Forest is a Crane Bell, and you reach it with a short climb. Look for two walls with scratched X marks and climb them with Space. The full route is in the first Crimson Forest bell walkthrough.
The Illusion of Inanis quest starts at this bell. You can follow it in the Illusion of Inanis quest guide. Everything else hidden in the area is listed in the Crimson Forest collectibles roundup.
Keep moving through the forest after the bell until you reach the Village of Lu. The story then continues with Heartless Remnants and the well.
