I have a very bad flu and not sure if I'm prgnant *** help me to what is best to drink for the flu??

Just like the old wives tale, it's chicken soup (mushroom soup if you're a veggie).
It has just the right balance of electrolytes.
You could also try sports drinks if you're not into soup.
Just stay well hydrated (fluids and electrolytes) and you should kick the flu in a couple of days.

Water and tea is good to drink for the flu too. You may find this helpful too: How To Fight The Flu Naturally

You got some great advice, but if you may be pregnant, you might want to visit your doctor if you don't show major improvement in the next few days.

All the above is good advice. Make sure you're taking plenty of warm fluids. When I had flu over christmas I used pomegranate juice, packed with Vit C and more antioxidants than most other fruit/veg. Take it easy for a few days and if you're not any better, as Devorameira says, see your doctor.
Feel better soon.