In this context 'spread' means the amount of food available. A big spread would give more choice, such as bacon, eggs, toast, sausages, etc. A big spread could also be a range of cereals, such as: weetabix, cornflakes, bran flakes, captain crunch, etc. The alternative is to use 'spread' as Sara has suggested, to butter your toast. Although her sentence using 'elaborate' does suggest that it could also be a bigger spread (selection) of food.

In the sentence, spread was used as a noun. It pertains to food available. In the sentence it means, nothing special for breakfast because mom is not around, so they'll just have cereal instead.

Hello, in this case spread is a noun, means a meal, especially one for a special occasion with a lot of different dishes arranged on a table. So a spread means a lot of different and tasty food <3

The father was not willing to prepare an elaborate breakfast for his son (we spread butter on a toast, etc.).