I'm squeezing my clutch handle and can just get the clutch to disengage . How do you adjust the clutch on these bikes, I know very little on this but usually always figure it out . Any help appreciated . I adjusted the cable to about as much as I can.

Have you checked the manual for your bike in the Tech Library above, in the tool bar? Each manual explains the procedure clearly, often with pictures.

If it feels like its lifting for the full movement of the handlebar lever--or close to full movement--i'm thinking there's something internal going on with the clutch. Is the clutch dragging --" hanging on in gear" & trying to pull you along when you want to sit stationary in gear.

No ,its not trying to pull its as if its got to much clutch and needs to release it.

Umm--umm umm. So am i thinking back to front. Is it slipping, as in revs rise without acceleration in speed. Sorry if i'm not quite on the case. DT125B according to this link, has adjustment screw 25 on the actuator which you could back off a bit. I was thinking yours is the different shape motor like 175 in 1975. Just need a bit more clarity of how it's behaving please. Is clutch burnt out. You'll soon know by smelling the oil by removing the dipstick by the kickstart--trans oil i mean.
www.partzilla.com/catalog/yamaha/motorcycle/1975/dt125b/clutch