Here some pic for you. I'm ok about Disk brake caliper mount standard for frame and fork. I beleive my frame have the 51mm International standard. But the mount doesn't look like any other mount saw when I googled it. What you guys thinks.

I freecycle a set of disc hub at my bike coop. The front already have a disc 180mm attach with 6 torx bolt says Fuji on the hub. The rear is Quando, no disc for that one but a cassette 8speed that look new. (not in the picture).

With the bike coop I have the choice between 7 disc brake caliper.

TEktro IO, Lyra or Aquila. Says Lyra and Quila are "Ball bearing cable actuated mechanical disc brake" ??? what exactly is that?
other choice are Shimano BR_M416 front or rear and Shimano BR-M495

They are all mechanical and takes 160 rotor. I beleive they all take V-Brake lever.

Thank for you advise everyone.