There’s real and significant difference between the Roman Catholic teachings on the sacraments and Reformed ones. Here, in a nutshell, are some major differences:
Sacraments are the instrumental causation of the blessings of union with Christ. The work of the Holy Spirit is ‘enclosed’ within the administration of the sacraments. In other words, the sacraments bring about union with Christ because the Holy Spirit is contained in the water of baptism and the bread and wine of Communion.
The Holy Spirit brings the individual directly into fellowship with Christ. The sacraments are signs or seals of that fellowship with Christ. The sacraments are subordinated to the joint action of the Word and Spirit. In other words, the Holy Spirit is the one who brings a believer into union with Christ. The Holy Spirit, alongside the Word, effect the union. The sacraments are signs that the union has taken place.