Assuming that they are (for example) strings, try:
SELECT myColumn1 + myColumn2 AS DisplayName FROM myTable
"I Modified the question sir."
The answer is still the same - you just have to expand it a bit:
select r.First_Name,r.Email_Id,r.City,r.State,e.industry_type,
'[by-' + r.First_Name + ',' + r.Email_Id + ',' + r.City +
',' + r.State + ',' + e.industry_type AS FullDetails
from Registration as r
inner join Experience_Detail as e
on r.Login_Id=e.Login_Id