The Regina Cæli or Regina Cœli … is an ancient Latin Marian Hymn of the Catholic Church.

The Regina Coeli is sung or recited in place of the Angelus during the Easter season, from Holy Saturday through the Saturday after Pentecost.

Catholic encyclopedia on topic (“Regina Coeli”): https://www.newadvent.org/cathen/12718b.htm

Latin text

Regina cæli, lætare, alleluia:

R. Quia quem meruisti portare, alleluia,

Resurrexit, sicut dixit, alleluia,

R. Ora pro nobis Deum, alleluia.

Gaude et lætare, Virgo Maria, alleluia.

R. Quia surrexit Dominus vere, alleluia.

Oremus.

Deus, qui per resurrectionem Filii tui, Domini nostri Iesu Christi,

mundum lætificare dignatus es:

præsta, quæsumus, ut per eius Genitricem Virginem Mariam,

perpetuæ capiamus gaudia vitæ.

Per eundem Christum Dominum nostrum. R. Amen.

English text

Queen of Heaven, rejoice, alleluia.

For He Whom you deserved to bear, alleluia.

Has risen, as He said, alleluia.

Pray for us to God, alleluia.

V. Rejoice and be glad, O Virgin Mary, alleluia.

R. For the Lord is truly risen, alleluia.

Additionally is often added (via St. Joseph’s Missal text)

Let us pray.

O God, Who by the Resurrection of Thy Son, our Lord Jesus Christ, vouchsafed to give joy to the whole world, grant, we beseech Thee, that, through the intercession of the Virgin Mary, His Mother, we may attain the joys of eternal life. Through the same Christ our Lord. Amen.

As some people may be unaware of the Angelus prayer:

The Angelus is a short practice of devotion in honour of the Incarnation repeated three times each day, morning, noon, and evening, at the sound of the bell. It consists essentially in the triple repetition of the Hail Mary, to which in later times have been added three introductory versicles and a concluding versicle and prayer.

https://www.newadvent.org/cathen/01486b.htm

https://infogalactic.com/info/Angelus