A dot placed above or below a note tells you to play it staccato. Staccato means to play a note short and separate from other notes. To play a note short, lift your finger off the key as quickly as possible.
This time signature is called the three four time signature. It tells you there are three beats in each bar. Three four time is also known as waltz time. Always select a waltz rhythm on your keyboard before you play songs in ^ time.
On the recording there are three drumbeats to introduce songs in ^ time.
A dot after a half note means that you hold it for three beats.