In our rails 6 project I want to export active record data to excel file and save xls file into S3 bucket without storing xls data on local db and send file link to email and provide download xls feature from email. Please help me.

1. Create a model which holds a exported file

# app/models/csv_export.rb

class CsvExport < ApplicationRecord
  has_one_attached :file
  # ...
end

Configure ActiveStorage that it uses S3 as a provider. See https://medium.com/alturasoluciones/setting-up-rails-5-active-storage-with-amazon-s3-3d158cf021ff

2. Create a export job which creates a new CsvExport with data

# app/jobs/csv_export_job.rb
require 'csv'

class CsvExportJob < ApplicationJob
  queue_as :default

  def perform(csv_export_id)
    csv_export = CsvExport.find_by(id: csv_export_id)
    csv_export.file.attach \
      io: StringIO.new(csv_string), # add csv_string call here
      filename: filename
    # ...
  end

  private

  # ...

  CSV_COLUMNS = %w[id name email].freeze

  def csv_string
    CSV.generate(headers: true) do |csv|
      csv << CSV_COLUMNS
      # or whatever data you want to export
      User.all.each do |contact|
        csv << CSV_COLUMNS.map { |col| contact.send(col) }
      end
    end
  end
end

3. Trigger job

e.g. from a controller action

csv_export = CsvExport.create(status: :started)
CsvExportJob.perform_later csv_export.id

I hope these examples will bring you to the right direction. If you need detailed help you can look at this article https://railsbyexample.com/export-records-to-csv-files-using-activestorage/