7 Biblical Feasts

1. Pesach
2. Feast of unleavened bread
3. First fruits
4. Shavuot
5. Yom teruah (day of shofar blast or noise 'teruah')*See explanation below.
6. Yom kippur
7. Sukkot

The List is in Leviticus 23.  Shabbat is also commanded here.  It is a PLEASURE to keep the sabbath!
And Rosh Chodesh 'The New Moon (Num 10:10,Ps 81:3)/Head of the Month (known as/celebration)'.  The Book of Numbers God speaks about celebrating Rosh Chodesh, to Moses.
We read of a time when ALL flesh will come to bow in worship of Him from Rosh Chodesh to Rosh Chodesh & from Shabbat to Shabbat.  In the new kingdom we will certainly be recognizing Rosh Chodesh & Shabbat, as well as Sukkot.  It says in Isa. 66:23 & Zech 14:16-19.

Rosh Chodesh is not a celebration of the moon or a form of moon worship. It is a recognition of the beginning of a new month. Rosh Chodesh literally means “head of the month”. When HaShem gave His Biblical calendar to His people there wasn’t a fixed calendar in place. The people did in fact use the heavens to determine their calendar – their days, weeks and months, seasons and years. One could look up at the moon in the evening and know just where they were in the month. They could look up at the stars and see what season it was or navigate based on the constellations. The sighting of the new moon signaled the new month to begin and it was a time for a festive family celebration. It wasn’t until the fourth century CE (aka AD) that Hillel II established a fixed calendar for the Jews in the diaspora. Because the Jews had been dispersed from their land and were living among the nations, they needed to have a fixed calendar in order to keep HaShem’s holy days. Hillel II established this calendar based on mathematical calculations and it was accepted by the Sanhedrian. This is what today is referred to as the Jewish calendar.      Source:  followingtheancientpaths.wordpress

*Yom Teruah is the only one which is given no reason for its celebration, and has become known & celebrated incorrectly as Rosh Hashana...

Today few people remember the biblical name of Yom Teruah and instead it is widely known as "Rosh Hashanah" which literally means “head of the year” and hence also “New Years”. The transformation of Yom Teruah (Day of Shouting) into Rosh Hashanah (New Years) is the result of pagan Babylonian influence upon the Jewish nation. The first stage in the transformation was the adoption of the Babylonian month names. In the Torah the months are numbered as First Month, Second Month, Third Month, etc (Leviticus 23; Numbers 28). During their sojourn in Babylonia our ancestors began to use the pagan Babylonian month names, a fact readily admitted in the Talmud:

“The names of the months came up with them from Babylonia.” (Jerusalem Talmud, Rosh Hashanah 1:2 56d)         Source:   Nehemiah Gordon's write-up.