You can access Scoot website at the following link.
Scoot web site
However, you are unable to retrieve your booking by your own email address, because the reservation was made through Giamso Tours.
If you wish to add checked baggage allowance, meals and view your itinerary, etc. please follow the steps below to login to Scoot website with your airline reference number (written on your e-Ticket receipt under the basic info “Airline Reservation No” (6-digit alphanumeric)).
For more details, please refer to "How do I find my airline reservation number on e-Ticket receipt?".
Scoot Airline Login as following:
Manage booking from Scoot Website as below:
2. Enter your 6-character Scoot booking reference: (Please skip the email address)
3. Passenger First Name:
4. Passenger Last Name:
5. Origin City: (Please choose from drop-down list)
6. Destination City: (Please choose from drop-down list)
After successful login, you are able to add on some ancillary items (baggage, meal, seat selection, etc.) and the fees shall be payable to airline directly.