If You Are a Catholic Returning After Time Away
The short way back for the baptized Catholic: Confession, Mass, and a parish.
The way back is remarkably short.
Go to Confession. This is the single door that reopens everything. You do not need to have it polished into a speech; the priest will help you. Bring what you can honestly remember and name, however long it has been: this is exactly what the sacrament is for. If it has been a long time, it may help to schedule a time with a priest to talk through your return and prepare for Confession.
Return to Mass. Once reconciled, come back to the Eucharist, which is the point of the whole return. You do not need to remember every response or when to stand and kneel; the rhythm of the Mass comes back quickly, and no one is watching to judge.
Reconnect with a parish. Find a local parish, learn its Mass times, and let yourself be known there over time. You are rejoining a family, not just resuming an obligation.