Hello
If I just want to use SKP to design below liner actuator position (A,B,C) without having mechanical design software like Solidwork, Fusion360, etc., is there any idea how to get this right fixing position ?

Maybe if you just share your approach, I may get idea how to finish this design with only SKP.

*BTW I am not mechanical engineer so I still learning what is right way to place this liner actuator to open cabinet door. Please feel free to suggest if you know how to install this part.

We have two cases:
open actuator - 20
closed actuator - 15
You draw lines of an open door. on it you define the mounting point (C) of the actuator. From the pivot point of the door (A), you draw a circle with a radius of A-C. this way you get point C '. From point C you draw a circle equal to the open actuator (20) and from point C ‘a circle equal to closed (15). The two intersections of these circles B and B’ mark the attachment point of the actuator to the cabinet. If they intersect outside the cabinet or in the wrong place, change the A-C radius.

However, you have to remember about SU ailments. Converts circles to polygons and errors may result. To minimize them, the number of segments in the curve should be increased.This is one of the reasons that limits the use of AE to simpler tasks

To avoid the issue with SketchUp’s segmented circles, you could use my circle intersect extension, available from SketchUcation. It finds exact intersections of the real circles.