How will it work if at my last court date the judge said I will be allowed supervised visits with my daughter supervised by my grandma?

You would need to look at the specifics in your parenting plan or court order to see how the schedule works. Generally, you would work with grandma and the other parent to set the time and grandma will need to be present at all times during the visit. Consult with your attorney (or an attorney) if you aren't sure how to set this up or what is or is not allowed under supervised visits. Best wishes.