When Jesus died and rose from the dead, didn’t He do away with all the oldestament laws, so that we do not need keep them?

Yes of course; the Roman Jesus who was designed by Rome came to get rid of the Jewish old testament and it’s commandments, so that we may all become followers of the Roman catholic Christian church. 

But the Hebrew Jewish Yeshua came to do the contrary: When Yeshua died and Rose from the dead, He did it for you, you did not do it for yourself. 

So for you to be able to connect into that reality you need to keep his seasons and commandments written in the old testament.

It is just like my children, I am their father, I am a man of God, but it doesn’t necessary mean that because am their father they can do what I can do or relate to God on my level.

I need to teach them the principles that makes me a man of God, when they learn and obey (keep them) they also become children of God.

You saying that Yeshua died and rose from the dead is just a story any one can quote, (even homosexual people declare the same thing for their lives). 

But to claim that he did it for you, you must also be in fellowship with His seasons (walk as He walked), if He kept the Sabbath and the day of Yomkippur as a Jew then we also need to keep it.

Those who claim that he died and rose, and they need not to do anything, because it was all done for them. Such people are quoting the Catholic doctrine and the teachings of the pagan Jesus of Rome. 

Here you can read about where the name of Jesus comes from

http://clifestyle.org/is-jesus-a-pagan-name-part-1

Here is the link below that reveals the real meaning of the Messiah who died and resurrected, click on the link below to read

http://clifestyle.org/salvation—the-word-salvation–originates-from-the-hebrew-word-called-yeshua