If you just want to have a look, you could just print them:
conv = nn.Conv2d(
    in_channels=100,
    out_channels=5,
    kernel_size=3,
    stride=1,
    padding=1,
    groups=1)
print(conv)
> Conv2d(100, 5, kernel_size=(3, 3), stride=(1, 1), padding=(1, 1))

Otherwise if you need to access them, you can do it directly:
conv.in_channels
conv.out_channels
conv.kernel_size
conv.stride
conv.padding
conv.groups

Is this what you are looking for?