Links:
Casters: https://amzn.to/3ykbODB
Pockethole clamp: https://amzn.to/3OPJ2l2
Pockethole kit: https://amzn.to/3R6BRqe
Basic Pockethole kit: https://amzn.to/3P5suoT
2.5 in pocket screws: https://amzn.to/3Rd3uhv
Grain N Gear workbench video:    • Easy Workbench With Casters no glue 2...  

Cut List:
approx 8 2x4s (kiln dried) 8 feet long
Outside legs
18 inches (6)
33 inches (4)
31 inches (4)
6 inches (4)
Inside span
30 inches (6)
27 inches (4)
total 676 inches
two 33 inch square plywood sheets (3/4 inch)