As far as blues playing goes, most beginning guitar players seem to be happy with playing Minor Pentatonic Solos or Riffs.
Once you get more experience with your Blues playing you may want to try some different ideas.
Have a look at the following Chord Sequence:
A D A A
D D A A
E D A E
This is a typical major Blues sequence.
To play solos and melodies over this sequence you can use Major arpeggios for the A, D and E chord.
You can also use the A major scale. You can play the A major Pentatonic, but it is also possible to play the A minor Pentatonic is some places. The A minor Pentatonic does have a grittier sound compared to the Major Pentatonic Scale.
the notes for the A minor Pentatonic are: A C D E and G
the C and the G are the crucial notes in the scale: the C is the minor 3rd and the G is the dominant 7, both notes will give the scale that particular gritty sound.
The notes for the A major Pentatonic are: A B C# E and F#
The C# and the F# are the crucial notes in this scale: the C# is the major 3rd, which creates a somewhat sweeter sound compared to the minor third in the A minor Pentatonic Scale. The F# is the major 6th which is responsible for the less gritty sound compared to the G —dom 7th—- of the A minor Pentatonic Scale.
Experiment with both scales.
A way to remember both scales is: Treat the A minor Pentatonic as the first three notes of the riff of “Smoke on the Water”. Those three notes are the start of the minor Pentatonic Scale.
The A major Pentatonic can be remembered by the first three notes of the song “My Girl” by the Temptations. Those first three notes form the beginning of the Major Pentatonic Scale.
Try playing those first three notes of both those songs in any place on the fretboard to see where your positions are.
Good luck and hope to see you soon again,