What do with baby

looking for activities to do with my 3 month old. We play all the time and sing and I hold her and dance with her. I teach her how to roll over although she can roll over on her on when she want ( lazy like her dad lol) we play with balloons, she play with her feet she loves to lift her self into a sitting position but cannot yet sit up without support but she will not sit laying back or she fuss. We read at bed time. I’m looking for some activities or things I do can with her to keep her little mind learning and developing she is currently hitting all her milestones but sometimes I feel I’m not teaching her enough.