CIO-2+I2 ------> I- + ClO3
H+
You were talking about I(-) and not of I2.
I will not simply write down the equations, but I'm willing to help you with the reactions.
First, what do you think are the reaction products of ClO(-) and I(-)? First determine these (you should have this info available, otherwise you could not solve this equation).
The other one, that is reaction between I2 and S2O3(2-), and not between I2 and S2O3. The compound S2O3 does not exist, the ion S2O3(2-) is the well-known thiosulfate and this reaction is very well known in iodometry.
In the latter reaction I will hint you. I2 is converted to I(-) and S2O3(2-) is converted to S4O6(2-), tetrathionate ion. With this info you should be able to balance the equation. No other ions and/or molecules are involved, just I2, I(-), S2O3(2-) and S4O6(2-).
Success!