I'm not sure what you are asking. Appropriate foundation for paving? It should be firm & flat with a slight grade to prevent pooling.

Are you considering concrete (poured or prepoured slabs), stone(crushed or pavers) brick, wood, tile, asphalt... Etc? Is it to be flexible or rigid? Will it be for patio, road or walkway? Each one of these materials and their uses have their own requirements when it comes to considering a foundation. Such a seemingly simple question as yours requires a lot of detail for a good answer.

Absolutely and any errors made here will be extremely costly to fix later.

The type of paving determines the foundation required. Decide on your paving first.

Useage - whether its going to have cars driven or parked on it (makes a massive difference) and whether its in your front garden rather than back garden - there are rules and regs in the UK about paving in front gardens now, to do with porosity, permeability and drainage.

we need a lot more info from you as already outlined.
May I ask is this an assignment task? if so at what level? then we can offer the best advice and even recommend other sources of information.

If you want to do a good permanent job it is worth spending the time on the base under your paving making sure your finished paving level is at leased two bricks below damp course, use a coarse grit sand bed a builders merchant will advise the right type and compact it if possible using a compacter and if possible have a fall away from your house then use cement to bed the paving using a rubber mallet on to your base not block paving requires a different method plenty of videos on youtube to show you how.