If you look at a column of squares they are numbered 1,2,3,4,5,6,7,8. If you look at a1 then the numbers go up a1, a2  a3, a4, a5, a6,a7,a8 as they move up the page.
If you are playing black it is very easy to get mixed up because you see the board from the opposite end. The letters run from h to a from left to right and the numbers run 8, 7 6 5 4 3 2 1 as you count the squares moving away from you.

The symbols for pieces.
R rook or castle.   N for knight.  Knight actually begins with a K but we use the letter K for King.
B bishop. Q Queen.  K King

If we want to show that the Queen goes to d3 we write Qd3. If we want to show that the Queen captures a knight on f3 we write Qxf3.  The x shows that something has been captured.
If a pawn is moving to e4 we simply write e4. We do not put in p for pawn.
This means that if the move says e4 this means that a pawn has gone to e4. If a piece has moved to e4 then there will be a letter in front.  Ne4 means that a knight has gone to e4.