A work breakdown structure is an outline of a project with varying levels of detail. It helps a project manager be certain that all products and work elements are identified so the project can proceed smoothly. Your project is building a bicycle and I have provided several sample WBS below. You job is to select the correct WBS of the ones shown below. You say you know nothing about bicycles and how they go together? You can use the image below to get your level 3 items and some strategic Googling to get your Level 2 items. This ought to allow you to put it all together:

SADDLE HEADSET STEM BRAKE LEVER SADDLE RAILS HANDLE BARS DROPPER SEAT POST SHIFTER LEVER HEAD TUBE TOP TUBE SEAT TUBE SEAT STAYS JETA TIRE PIVOTS DOWN TUBE SHOCK FORK HUB THRU AXLE CASSETTE PODE BRAKE CALIPER BRAKE ROTOR CRANK ARM NIPPLE CHAINRING RIM CHAIN STAYS REAR DERAILLEUR HOBBY DICS SPOKE DRIVETRAIN WHEEL PACING RALPH BR O 0 Mountain Bike Drivetrain Steering Wheelset Frame Chain Stay Handicare Brake Caliper Headset Chainring Stom Brale Rotor Top Tube Crank Arm Fork Spoke Seat Tube Rear Derailleur Head Tube Rim Down Tube O Mountain Bike Drivetrain Steering Brakes Seat Assembly Chain Stays Handlebars Front Rotor Saddle Chainring Stem Rear Rotor Saddle Rails Crank Arm Fork Brake Lever Dropper Seat Post Rear Derailleur Head Tube Brake Calipers Seat Tube O Mountain Bike Drivetrain Steering Wheelset Frame Chain Handlebars Thru Aude Head Tube Chainring Stem Tire Top Tube Crank Arm Fork Spoke Seat Tube Rear Derailleur Headset Rim Down Tube Mountain Bike Drivetrain Steering Wheelset Frame Chain Stay Handicare Tire Saddie Chainring Stom Hub Saddle Rails Crank Arm Fork Spoke Dropper Seat Post Rear Derailleur Head Tube Rim Seat Tube