Assuming bike is British and has British Thread
The first thing to remember is that the cranks move one way but actually work to move the BB shell in the reverse direction.
So on the left the cranks move anti-clockwise so turn the shell clockwise - hence the thread tightens turning clockwise. ( If the thread tightened A/C then it would work loose.)
On the right the cranks move clockwise so the shell will turn anti-clockwise - the thread tightens turning anticlockwise.
So to undo the left BB shell needs to turn anti-clockwise
The right needs to turn clockwise.
Next.
You have two sides to these old type BB's.
The fixed cup (right hand side ) which comprises of a BB shell (threaded as above) and a locknut (which will be threaded the other way so as it locks).
The other side is called the adjustable cup and is a single threaded shell with hexagonal sides.
You see bikes with the adjustable cup on the left and some bikes have it on the right - in the pic below and with yours it is on the left.
So what you need do is
a) Remove the bottom pic side first. This is on the right so undo by turning clockwise.
Then take the axle and bearings out.
b) You then need to look at pic 1. One part (usually but not always the bigger outer piece) is the locknut so needs to unscrewed. This will unscrew in a clockwise direction.
Then undo the BB shell which will undo in an anti-clockwise direction.
* Make sure you identify which nut is which*
a spanner will undo the small nut and the big ring with notches is undone with one of these (there is a smaller version commonly available).
Picture of Drive Side:
