The fastest way to learn the letter names of the piano keys is to use piano key stickers.
Click Here for a wide variety of options on Amazon. You can also pick these up at most music stores.
Another option is to cut the sticky portion a of post-it note and then cut it into small stickers to fit each key. Once you've done that, write the letter name of each piano key on each separate post-it note.
Middle C, the Music Staff and Ode To Joy
In Illustration #1 above, the blue circles show the group of 2 black keys, which are always followed by a group of 3 black keys. Notice that the C key is always the first white to the left of every group of 2 black keys. Middle C will always be shown as C4 on the virtual keyboard in every video lesson.
Illustration #2 below, shows the music staff for the right hand notes, (top - blue), and the music staff for the left hand, (bottom - red).
Each music staff, (top and bottom), is made up of 5 lines and 4 spaces. Music notes are placed on either a line or a space.
A music note is called a space note when the round note head is placed in-between the lines, (see blue note example below). A music note is called a line note when the round note head is placed directly on the line, (see red note example below).
If you're new to YouTube, it's a good idea to familiarize yourself with the two icons I have marked with arrows below. The "Enlarge Screen" icon should be used all the time, and the "Playback Speed" icon should be used if you need to slow down the tempo of video.
Ode To Joy - R.H. Melody
The right hand melody starts with your 3rd finger on the E, which is two white keys above middle C --- C4 on the virtual keyboard. Watch Video