For the spinning finger on the Gentlebean’s Fever stage:

You don't need to do anything other than press forward. Whichever direction the finger is pointing towards, you will walk in that direction when pressing forward. So you basically wait until the finger is in the right direction, press forward to walk there, release forward to make the finger change direction, etc. That means you might have to zigzag a bit to avoid all obstacles. Getting hit by the swinging logs when you're in the middle of the course should still be fine, you'll be slowed down but you won't fall over the edge, it's more important to focus on avoiding the holes in the platform.

For the arrow at the beginning of Manderville-Can Parade:

If your arrow is facing backwards, just face backwards.

If your arrow is facing left or right, I found that it helps to move your camera in the direction you want your arrow to go towards (if your arrow is going right, you want it to go counterclockwise, so you move your camera counterclockwise), and again only press forward to align your character with the camera.

Here's a gif that hopefully explains it better:



Worth noting that I am using the Legacy Type movement settings (you can change it under Character Configuration > Control Settings > General), might be worth a try see if it helps!

(I made the change back in ARR after someone recommended it to me because I kept eating Titan's Landslides, and it feels sooo much better to me than the Standard Type that made me feel like I'm moving a truck, it's a question of preference I guess)