You can still carry up the gifts if you aren’t Catholic. All you have to do is go to the back of the Church whenever you are called (talk to the priest or someone beforehand) and then you will walk up with some other gift-bearers to the altar where the priest and maybe some altar servers will take the gifts and maybe shake hands with you. You then go back to your seat.
Also, if you aren’t Catholic, please be aware that the Communion at the end of Mass is very important because it is a physical encounter with Jesus Christ, truly present and very real. If you do not hold this belief and are not initiated in the Church you should not take sacrament; to Catholics this is very important and sacred. God bless you and your deceased loved one. I will offer prayers for his/her soul.
By Thy resurrection from the dead, O Christ, death no longer hath dominion over those who die in holiness. So, we beseech Thee, give rest to Thy servants in Thy sanctuary and in Abraham’s bosom. Grant it to those, who from Adam until now have adored Thee with purity, to our fathers and brothers, to our kinsmen and friends, to all men who have lived by faith and passed on their road to Thee, by a thousand ways, and in all conditions, and make them worthy of the heavenly kingdom.