My 8 years old brother is always toe walking. Will he outgrow it?

See a specialist. A thorough evaluation is needed to determine why a child may be toe walking before consideration of treatment options. This includes the timeframe that the child has been walking like this, milestones, life stressors and congenital and neurological disorders that may be present. Conservative care includes physical therapy, serial casting and monitoring. If this fails, surgery may be indicated.
No. At this age he should be walking in a normal pattern. He needs to be examined to find the cause and have it corrected.