Numbers 9:5

And they kept the Passover in the first month, on the fourteenth day of the month , at twilight , in the wilderness of Sinai ; according to all that the Lord commanded Moses , so the people of Israel did .

and they did so in the Desert of Sinai at twilight on the fourteenth day of the first month. The Israelites did everything just as the Lord commanded Moses.

And they kept the passover on the fourteenth day of the first month at even in the wilderness of Sinai : according to all that the Lord commanded Moses, so did the children of Israel.