You can use the belt for first 4-6 weeks then it's more important to work on basic core muscles strengthening and scar tissue management this will help in long term .
As the core muscles are cut they become weak hence causes back pain later in C sec patients .
Next Steps
Get in touch with a physiotherapist who can design basic post operative core muscles strengthening and manipulation of scar as a tight scar will lead to adhesions and further weakening of muscles .
Health Tips
Keeping lower tummy tucked in is a good way to start , hold the tummy tuck for few seconds n leave .
Practice the same while walking , sitting and also during nursing the baby , this will instantly put your back in upright position till the hold is maintained.
Take Care .