The Torah portion is Ki Tisa, Exodus 30:11-34:35. In synagogues using the Triennial system, 5783 is year 1 and the Torah reading is Exodus 30:11-31:17.This parshah contains a number of well-known highlights of the Torah, including the sin of the Golden Calf; Moses shattering the original Ten "Commandments"; Moses asking to see G-d's glory and G-d saying that mankind cannot see His face but only what comes after Him.
There is a special maftir portion (the final piece of the Torah reading) for Shabbat Parah: Numbers 19:1-22. This passage speaks of the offering of the Red Heifer (Parah Adumah), which purifies people from contact with the dead. It is a reminder to purify for Pesach (Passover), which is coming very soon!
The haftarah is for Shabbat Parah, Ezekiel 36:16-38. Like the maftir portion, this haftarah speaks of purification.
In synagogues using the Sephardic tradition, the Haftarah is Ezekiel 36:16-36.