Can i stay sitting for a long time 3 months after microd with hemilaminotomy?

Always better to: Change positions often, and stretch frequently. But 3 month after a microdiscectomy/hemilaminotomy procedure, the risk of recurrent herninated disc although still possible should not be such that you have to be on any particular restrictions. The first 6 weeks following such a procedure is when restrictions is important. So no worries, but pay attention to proper body mechanics.