1954 house: bathtub and shower not an easy flow or drain

[kcg5562]

My partner and I moved into the house they grew up in. The sink in the main bathroom and the toilet has awesome water flow. The tub has some water flow, but not a whole lot. The flow from the shower however has none what so ever. I found the shut off/turn on valve outside under the window.
The drain takes forever to drain water. I have tried liquid plumber and CLR. at different times not using both at the same time.
I want to be able to take a bath, before I go to bed after a long day work. I wanted to attach pics, but I am unable to send pics at this time.

 

[Reach4]

On many tubs, you clean the hair out by unscrewing the plate over the overflow, and lifting the actuator out.

 

[Sponsor]

 

[kcg5562]

On many tubs, you clean the hair out by unscrewing the plate over the overflow, and lifting the actuator out.

Thank you I will try unscrewing the plate at the drain. My spouse said the last time that tub had been used was sometime back in 2009