Is CH3 a ortho-para directing group or meta directing group? please give the list of all ortho-para directing and meta directing groups.
There's a simple rule to know whether a group is o-p directing or m directing. If it donates electrons to the ring, the cumulative electron density increases more at the ortho and para positions rather than at the meta positions, thus directing an electrophile there.
If it withdraws electrons from the ring, the density decreases more at the ortho and para positions rather than at the meta positions, thus directing the electrophile towards the meta positions.
You can usually check this by resonance and inductive effects. Also, in some special cases, like that of pyridine, the lone pair does not go into conjugation with the ring and thus the N atom of pyridine is electron withdrawing and not donating.
Following this, CH3 is o-p directing.