LM358 differential voltage and amplifier circuit
First disconnect second stage input from first stage output.
Biasing (DC) of Pin 2 and Pin 3. Pin3 is held at approximately 1.4 volt and Pin 2 at about 12 volts. Your inputs at those Pins have to be of level which would not require any amplifier circuit. A resistor from Pin2 to ground is required to bias the pin properly. Else connect it to input through a series resistance of 10K. Use coupling capacitors to avoid disruption of dc condition of pins.
Feed back. Pin 2 is fed back through 100K (R4). The present configuration gives stage gain of (R4/R2 = 0.25). R2 value (input impedance) should be (for example) 10K for gain of 10.
Preferably use  Variable Resistor (one for a pair) for setting DC conditions of Pins. Later on, you can use fixed value resistance.
After fixing stage 1 check stage 2 dc conditions, connect stage 1 output to stage 2 through a coupling capacitor and check.