I have done a whole bunch of fasting over the past eight years, and have posted lots of information on this forum regarding juice fasting how-tos and whys. I invite you to browse through my posts, and the posts of others on this forum before you ask further questions.
Juice absolutely can and will support you to your goal. Become as familiar with it as you can before beginning, to remove some of the mystery, and you will feel more confident in your fast.
Liver Flushing prior to beginning is absolutely not required. You might do that separately at another time if you are a beginner. Liver Flushing is wonderful, but altogther it could be overwhelming for your first go.
Feel free to drink unsweetened herbal teas, or sweeten with stevia. You should drink 3-6 cups of freshly pressed juices during your fast, fruits in the am, veggies in the pm.
All this is repeated many times in my posts below, along with colon cleansing protocol, which is something you need to understand and follow.
If you are at all hesitant about fasting, start with a short fast of 5-7 days. It takes three days to remove the major debris from your colon and allow the body to begin the fasting process, so I would go at least five days. If you are feeling well at day 5, go to 7. If you still feel well, go to 10! By day ten you will have a real feel for what it is all about. You will be about ten pounds lighter and will have experienced the light, clean feeling you get when the task of digestion is removed from your body, allowing it to cleanse, detox and heal.
READ! Inform yourself about fasting before you begin. Then, if we can help you in any way, let us know!