You can start with Kapalbhati. It is a pranayama yoga technique that is performed in a seated position. It focuses on the abdominal area, exhaling air by using our abdominal muscles. That helps in digestive and excretory issues. You can refer to this article if you want - https://www.vedyou.com/blog/six-dif...ts-benefits/ There are other shatkarma techniques explained as well. I hope it helps you with your problem.