Any way to find camshaft lift & duration with camshaft already in engine.

Maybe yes;
Lift is easy to check
Duration is not, but can be done by degreeing the cam.

Some cam lifts proclaim the cam that they appear on.
Like a 292/292 cam... the duration is known and there are not a lot of contenders in that arena.
Others like the 268/276; everybody has one and the lifts are all over the place, so you just can not guess on this one.

Some guys, not me, can guess the size of the cam by the relationship of idle-speed to manifold vacuum, and others by the relationship of idle-lope and idle- rpm; also not me.

The only sure way is to degree it and measure the lifts.