grouping in Grid

You can group the data before passing it in DB or in expression.
Or
You expecting something different?

assume that I have a field - Job Type  for that field I have values Software for 2 rows then I need group that two rows into single row

You have to aggregate data.
Hope you are expecting similar..

a!localVariables(
  local!employees: {
    a!map(name: "John", jobType: "Software", salary: 50000),
    a!map(name: "Sarah", jobType: "Software", salary: 60000),
    a!map(name: "Mike", jobType: "Testing", salary: 45000),
    a!map(name: "Lisa", jobType: "Testing", salary: 55000),
    a!map(name: "Tom", jobType: "Management", salary: 70000),
    a!map(name: "Emma", jobType: "Management", salary: 65000)
  },

  /* Get unique job types */
  local!uniqueJobTypes: union(local!employees.jobType, local!employees.jobType),

  /* Aggregate data by Job Type */
  local!aggregatedData: a!forEach(
    items: local!uniqueJobTypes,
    expression: a!localVariables(
      local!currentJobType: fv!item,
      local!filteredEmployees: a!forEach(
        items: local!employees,
        expression: if(fv!item.jobType = local!currentJobType, fv!item, null)
      ),
      local!validEmployees: reject(fn!isnull, local!filteredEmployees),
      a!map(
        jobType: local!currentJobType,
        employeeNames: joinarray(local!validEmployees.name, ", "),
        totalSalary: sum(local!validEmployees.salary),
        employeeCount: count(local!validEmployees)
      )
    )
  ),

  a!gridField(
    label: "Employees Grouped by Job Type",
    data: local!aggregatedData,
    columns: {
      a!gridColumn(
        label: "Job Type",
        value: fv!row.jobType
      ),
      a!gridColumn(
        label: "Employees",
        value: fv!row.employeeNames
      ),
      a!gridColumn(
        label: "Count",
        value: fv!row.employeeCount
      ),
      a!gridColumn(
        label: "Total Salary",
        value: fv!row.totalSalary
      )
    }
  )
)

Make use of aggregation in the queryRecordType(). You can use a!aggregationFields() when defining the fields for querying the record.