Here are some contacts to ask for prayers online:

EWTN: https://www.ewtn.com/giving/prayer-request

Divine Mercy Marian Helpers: https://www.thedivinemercy.org/prayer

Lourdes: https://www.lourdes-france.org/en/intention-priere/

Fatima:  https://worldfatima.com/en/prayer-petitions

Relevant Radio: https://relevantradio.com/prayer-requests/

Rosary for the World (an initiative of the Mary of Nazareth Association): https://rosaryfortheworld.org/intention

Carmelite Sisters of the Most Sacred Heart of Los Angeles: https://carmelitesistersocd.com/prayer-requests/