Potentially able to look it up here for intel processors: https://ark.intel.com/content/www/us/en/ark.html
On a Mac, open the Terminal and paste in the following command:
sysctl -a | grep machdep.cpu.leaf7_features
The output will look like this:
machdep.cpu.leaf7_features: RDWRFSGS TSC_THREAD_OFFSET SGX BMI1 AVX2
SMEP BMI2 ERMS INVPCID FPU_CSDS MPX RDSEED ADX SMAP CLFSOPT IPT SGXLC
MDCLEAR TSXFA IBRS STIBP L1DF SSBD
The AVX2 protocol is listed in the features.
For PCs, refer to the above URL with the processor model (For example Intel(R) Core(TM) i5-9400F CPU @ 2.90GHz 2.90 GHz)