Without an equality sign the given expression can't be considered to be an equation.
If you mean: y = 2x-3 then the slope is 2 and the y intercept is -3
If you mean: y = 2x+2 then the slope is 2 and the y intercept is 2
If you mean y = 2x-3 then it is a straight line equation whereas 2 is the slope and -3 is the y intercept
If you mean y = 2x-3 then the parallel equation will have the same slope of 2 but with a different y intercept
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