How To Create rotary and linear motion using barrel cam on single shaft ? Pls Advice...

The scale of the mechanism makes it harder to imagine any useful solution but I suspect it was made this way to show all the components in as compact an image as possible.

In a compact design... the followers could be used to drive components linearly on either side of the shaft. You'd need something to 'house' the follower.

With a large cam, the followers could be far outside the area of a fixed bearing support. Then it's just a matter of finding a suitable way to drive the mechanisms. A spherical end pushrod gives you even more offset capability.

Not that this type of motion isn't more easily obtained with other designs... but you never know when some idea you thought was never going to be useful turns out to be a feasible solution. That's why 'we' study all these crazy mechanisms.

I've used a similar mechanism (we called it a "wobble mechanism") when designing a reciprocating saw. The two opposite linear motions provided a counter-balance that reduced the vibration in the saw.