To answer your question it all depends on your current bodyweight/muscle mass: So if we were to take someone weighing in at 80kg we would take that number and multiply it by the given numbers down below, giving you your 1 rep max for your bench, squat and shoulder press. Through this you can decide/narrow down which plate set/bundle would be best suited for you.

Example:
Person weighing 80kg

Bench 1 Rep Max = 45kg (.56 x bodyweight)
Squat 1 Rep Max = 65kg (.81 x bodyweight)
Shoulder Press 1 Rep Max = 35kg (.44 x bodyweight)

Yes the plates are available bundles/sets. Here are the available sets for purchase:

'60KG Bumper Plate Set' = 2 x 5kg, 2 x10kg, 2 x 15kg
'100KG Bumper Plate Set' = 2 x 5kg, 2 x10kg, 2 x 15kg, 2 x 20kg
'150kg Bumper Plate Set' = 2 x 5kg, 2 x 10kg, 2 x 15kg, 2 x 20kg, 2 x 25kg

The recommended set/bundle for the person mentioned above would be the 100kg bundle, as it gives plenty of possibilities for progression and will challenge the individual.