The voltage becomes zero when the load is connected
I assume there's a question hiding in there somewhere. Let's pretend the question is, &quot;Why is the voltage across a 10-ohm load zero?&quot;
Let's start with the basics. Check to see that IN1 and IN2 are actually different. One should be high and one should be low. Are you letting them float? If you're driving them from something like an Arduino, and you've screwed up your code, it's entirely possible that both inputs are being commanded to the same level. In that case, both sides of the load will be driven to the same level, and the current through the load will be zero.
If the input levels are correct, shrug. Who knows? You've provided no information, especially voltages at various points on the circuit. At a guess, it's because your MOSFETs are not getting any gate drive.
Why would that be? Any number of reasons. You might have miswired the IR2110s. You might have connected the FETS backwards. You might have used the wrong component values - for instance, if you used 10k resistors instead of 10 ohm resistors for R1, R2, R5 and R6, that would explain it.
But there's no way to tell without you doing a lot more work. Among other things, the accuracy of your schematic is not exactly without question - if you got the load supply voltage wrong (300 V instead of 12), who knows what other errors you've made?
So. Check to see that ALL of your grounds are actually tied together. Check to see that both your +5 and +12 are present at every point they should be. Check for the value of Vs on both drivers - it should be about +12 on one of them. Check to make sure that +12 is being applied to the correct pins of Q1 and Q3. Check the gate-source voltages of all the MOSFETs.