How to convert current source to voltage source when to current sources are in parallel?
By what i can see you diagram is wrong.
To convert the two current sources you convert the sources considering the parallel resistors as the figure below.

To convert the current source to a voltage source you first substitute the pair (current source)-(resistor in parallel) by a series association of a voltage source and a resistor with the same value as the resistor in parallel.
The value of the voltage source is given by the formula V=R*I.
Pay attention to the direction ofthe voltage source as it needs to have the same direction as the current source.
Applying the transformation leads to the following circuit.