You can’t just chose your own readings. You select from the choices that are spelled out in the rite for weddings. The first reading is from the OT and there are several choices. The second reading is from the epistles and there are several choices for that too. You cannot read from the Gospels.
The bride and groom should have received a booklet that shows what choices are available.
(Not likely, but, if this is a wedding at a Mass, it is prudent to check and make sure that there isn’t a requirment to use the “readings of the day” from the Sacramentary)