Finding ADC pins from Init code
According to the datasheet, Your device has 3 separate ADC modules with 16 input channels (not 2 or 3 channels as suggested in the comments to your question).  

From a snippet of your initialization code:  

  ADC1-&gt;SQR1 = (1&lt;&lt;6) | (3&lt;&lt;12) | 1;
  ADC2-&gt;SQR1 = (2&lt;&lt;6) | (4&lt;&lt;12) | 1;


it appears that ADC1 &amp; ADC2 are being used, and each of them is being configured to sample 2 different channels - so 4 in total.
ADC1 is sampling channel 1 &amp; channel 3.
ADC2 is sampling channel 2 &amp; channel 4.
See page 602 of the reference manual.  

To work out the physical pins these channels refer to, we go back to the datasheet - The section of Table 16 on pages 71 &amp; 72 tells us that channel 1 for all 3 ADC modules (ADC123_IN1) is on PC0/pin-8 of your STM32L476RG 64-pin package.
Similarly, channel 2 is PC1/pin-9 and channels 3 &amp; 4 are PC2/pin-10 &amp; PC3/pin-11.