Learn German: Ich würde ihn meinem kleinen Bruder geben. - I would give it to my little brother.

This sentence uses würde to express a hypothetical situation (would give). In these kinds of sentences, würde acts like a modal verb: it takes the second position, and pushes the main action verb (geben) to the very end of the sentence in its dictionary (infinitive) form.

Why use ihn if the English translation says 'it'? Doesn't ihn mean 'him'?

In German, pronouns must match the grammatical gender of the noun they replace. ihn is the accusative (direct object) form of er (he). If the thing you are giving is a masculine noun, like a sweater (der Pullover), you must use ihn to refer to it, even though in English we just call it 'it'.

Why is it meinem instead of mein?

The verb geben (to give) involves a direct object (the thing being given) and an indirect object (the receiver). The person receiving the item always takes the dative case. Because Bruder is a masculine noun, the possessive word mein changes to meinem in the dative case.

Why does the adjective kleinen end in -en here?

This ending is required by the dative case. After a possessive word that already clearly shows the dative ending (like the -em on meinem), any adjectives that follow it get the standard -en ending.