My tibia bone on my right leg fractured, without surgery I'm in a full length cast. How many days reqd to remove the cast and by when can I start walk?

Tibia fracture. You may be in the cast for at least 6 weeks depending on the fracture. If x-ray show good alignment and healing your doctor may put you in a shorter cast or fracture boot and let you start putting weight on it.
Varies. This varies with different types of fractures. Some tibial shaft fractures heal within 4 months, yet many may take 6 months or longer to heal.