Are you seeing improvements in mobility with the work you are doing?
Are you addressing movement patterns with your mobility work?
You want to get to the root of cause of your mobility restrictions.
Yes, start with the spine first.
If something isn’t right here the primary engines of the hip and shoulder will not move correctly.
Once restrictions/limitations with the spine are resolved move to the primary engines of the hip and shoulder.

Continue training. Smart training will help get things turned around.
Remain within pain free ranges of motion you can control without losing positioning.
Squat as deep as you can while maintaining control & maintaining an arch.
Start with the box squat.

During warm up incorporate the ranges you’ll be working within that day Get those positions warmed up and ready.  It is important to work in all planes of movement. Before and after training keep working within multiple ranges of motion. It may take time to get to where you want to be, however, keep chipping at it.

Initially removing speed and weight may be necessary to develop proper movement patterns for the skills you are working with. In the beginning, drill and skill work may be your workout. This will help build a solid foundation with your movement patterns,Just where things are at.
There are many aspects you can include to get a solid workout in while reinforcing correct mechanics and technique with skills.

As your mobility improves and you are able to maintain position/technique start working in the the other aspects.
Have you done the 14 day challenge 7 green lights?
This is a solid series to identify where work is needed.