This year in 2026, starting from the evening of Thursday May 21, it will be the biblical Festival of Weeks (Shavuot), and outside of Israel, Saturday May 23 is also observed as the second day of this festival by rabinnic ruling. The usual Torah reading sequence is paused. Instead, the following are read:
Exodus 19:1-20:23 (First day), Numbers 28:26-31
https://voices.sefaria.org/sheets/410246?lang=bi
Deuteronomy 14:22-16:17 (Second day), Numbers 28:26-31
https://voices.sefaria.org/sheets/37211?lang=bi
These links also include other bible readings outside of the Torah.
In addition, Book of Ruth is also read on the second day:
https://judaism.stackexchange.com/questions/122285/when-do-we-read-megillat-ruth
This is partly because the story of Ruth talks about harvest that is related to this season, and partly because Ruth accepted the covenant with the G-d of Israel like the people of Israel did many years ago during this season at Mount Sinai. See
https://en.wikipedia.org/wiki/Shavuot
It is customary to eat diary foods for Shavuot.
Happy Shavuot!