Hi every otai here I am a beginner of this field

Can anyone tell me...
What is the necessary skill needed to become a freelance web designer? Graphic design + HTML + CSS is enough? if not enough, what knowledge is a must / strongly recommended to learn?

And may I know generally the reasonable price for 1 page / project is how much?

If you encounter some client says 'I promise you I will pay RMXXX if your design is used', will you accept this job?