If the problem is "find the perimeter" just find the lengths of the three sides and add them! The distance from $\displaystyle (x_0, y_0)$ to $\displaystyle (x_1, y_1)$ is $\displaystyle \sqrt{(x_1- x_0)^2+ (y_1- y_0)^2}$. You are given the coordinates of the three points. Find those three distances and add.
You are trying to find the Incenter and Inradius,
and don't know how to find side lengths?
That's a bit like trying to cook and not knowing how to turn on the stove
Also, your diagram is faulty (if in 1st quadrant as the coordinates suggest).
I suggest the following:
1: change your labelling from 1,2,3 to A,B,C respectively
2: get some graph paper and plot your triangle correctly
3: come back with a new/correct diagram
4: show your work