What is the difference between a vector and a scaler in 1 dimension.

This can be very confusing when you start so it is a good idea to get a firm grip on the words.
There is no such thing as a one dimensional vector in Physics.
All vectors have at least two components corresponding to at least two dimensions.
That is there are two variables that can be varied independently of each other, over the full range of available numbers or scalars.
This requirement for variability over the full range is why +1/1 are not acceptable and direction meaning just forwards and backwards is not acceptable as a vector.
This distinction is of little consequence in ordinary everyday common or garden vectors.
But it becomes vitally important when you move on to study tensors.
Tensors have something called rank, rather than dimension.
The theory of tensors fills in the awkward spots in vector theory and answers some of these questions.
This is because tensors are also defined as transforming according to certain rules.
One of these rules of transformation is that scalars are unchanged by a transformation.
Examples of this are
Both temperature and frequency are measured as a simple single number.
Temperature is a scalar,
but frequency is not a scalar.
You will measure the temperature of a body the same, regardless of whether you are standing next to that body or moving towards it or away from it.
Temperature transforms from the standing still to the moving situation according to the equation
T' = T
Where T is the temperature in the standing still coordinate system and T' is the temperature in the moving one.
But the same cannot be said for the frequency of a wave emitted by that body.
This changes according to the motion by a much more complicated equation.
T' = T is one definition of a scalar ( as opposed to just a number).
In this scheme scalars are defined as tensors of rank zero, and vectors are defined as tensors of rank 1.
As such all the scalar  vector arithmetic works well.