To play the E note, pick the open 6th string.
Play the F note with the first finger of your left hand behind the first fret of the 6th string.
Play the G note with the third finger of your left hand behind the third fret of the 6th string.
Here is an example which uses E, F and G on the 6th string. A good way to memorize new notes is to name them out loud as you play. Try it with this example and also previous examples until you can instantly name any note you have learned.
Now try this 12 Bar Blues in the key of E minor which uses notes on all six strings. If you have trouble with any of the rhythms, practice them on one note while counting out loud.
A dot above or below a note indicates that the note is to be played staccato, which means short and separate from other notes.
To play a note staccato, lift the left hand finger off the fret as soon as the note sounds. If you are playing an open string, stop the sound with the right hand as soon as the note is played. Experiment with staccato in your own playing until you can do it naturally.