Which Chukim and Mishpatim is the Torah referring to?
Ramban, Seforno and Moshav Zekenim: 'Chukim' pertains to the Chukim of Sh'mitah and Yovel, and 'Mishpatim', to the Dinim of buying and selling that are connected with it.
Oznayim la'Torah: 'Chukim' pertains to the prohibition against tilling the land in Sh'mitah and Yovel
See Oznayim la'Torah who elaborates..
Why does the Torah insert the phrase "Viyeshavtem al ha'Aretz la'Vetach" here?