So you are asked, first, to integrate f(x, y)= x- iy along the line given by x= -1+ t, y= t, for t= 0 to 1. That is the same as the vector integration .
The second part is asking you to integrate f(x,y)= x- iy along two line. First along the x-axis from (-1, 0) to (0, 0) then along the y-axis from (0, 0) to (0, 1). Along the x-axis, we can take x= t- 1, y= 0 so the integral becomes . Along the y-axis, we can take x= 0, y= t so the integral becomes . The integral from z= -1 to z= i is the sum of those two integrals.