to open a seal you can overwhelm it with energy, have the one who placed it on you release it, or find a spell on this site that can break it.
As for calling a dead loved on you can do a seance which requires only people, you can use a black mirror, you can use a ouija board (not recommended), you can also try to summon them with your energy alone.
i would suggest a trained medium to help you do this and not doing a ouija board unless you are trained to do so or someone who knows what they are doing as ouija boards are very real and dangerous if not used properly blessed be sue x
thank you for all of your advice, as for the seal, I did it to myself with out realizing it. and as for the calling, i have tried all but the Ouija board, and that is because i do not like those things, I am supposed to be a mediator, but I lack the knowledge and openness to do so