I am not very good at reading music. Will I still be able to go through the 101 and 201 courses?
Yes. In order to go through the courses, you should have a basic ability to read both treble and bass clefs.
You do not need to be able to play the piano. Even though exercises are for grand staff (piano) we generally use notation software for playback.
You do not need to be a fast music reader. You can still learn while reading the music slowly. You will get better and faster at reading music as you progress.