Learn Russian: Моё поколение любит интернет.

It has to match the gender of the noun it belongs to. The word поколение (generation) ends in -ие, making it a neuter noun. Therefore, we use the neuter form for "my", which is моё.

Since a generation is a group of many people, why is the verb любит in the singular form?

In Russian, collective nouns like поколение (generation), семья (family), or группа (group) are treated grammatically as a single unit. Since поколение is a neuter singular noun (an "it"), the verb takes the singular "he/she/it" form любит.

Is the word интернет in the Nominative or Accusative case in this sentence?

It is in the Accusative case because it is the direct object (the thing being loved). However, because интернет is a masculine, inanimate noun (a non-living thing), its Accusative form looks exactly the same as its Nominative dictionary form.

Why does the verb end in -ит (любит) instead of -ет?

The verb любить (to love) belongs to the second conjugation group because its dictionary form ends in -ить. For this group of verbs, the present tense ending for "he/she/it" is -ит.