ADC with better performance
I need to sample voltage at a very high rate (say for like 10000 Hz) and with a very good precision(at least 10-12 bit ADC will do).


10Ksps and 12bit-resolution adcs are fairly common for onboard ADC. you should be able to find lots of mcus that have adc modules that can do that.

even for an external adc, that's not difficult at all. because of the speed, you are likely looking at a spi adc module.

precision is another matter.