I have scoliosis in my lower back so im used to occasional pain and stiffness there but lately i'm in constant pain sometimes so bad i can barely walk?

Scoliosis: Its important to note the severity of the scoliosis. If your symptoms are this severe & truly due to scoliosis then its time to see a spine surgeon, preferably one who is highly trained in scoliosis. You can always try pain management & other available conservative treatment, but if the condition is severe, none of these will treat the cause. Regardless, severe back pain needs a doctor's hands.

Isometric exercises: Isometric exercises to build up para-spinous muscle strength are likely going to help. These include swimming, stationary bike, rowing machine, yoga etc. Needs at least 3x/week one hour each time, make sure to warm up thoroughly first. A lumbar brace may give you some temporary relief. For any weakness/numbness, worsening or no improvement see a neurosurgeon or scoliosis specialist.