I think the easiest way that would give you the most control over your model, would be to write it from scratch
class MyResnet2(models.ResNet):
    def __init__(self, block, layers, num_classes=1000):
        super().__init__(block, layers, num_classes)
        
    def forward(self, x):
        x = 1.41*self.conv1(x)
        x = self.bn1(x)

        return x

from torchvision.models.resnet import BasicBlock
model = MyResnet2(BasicBlock, [3, 4, 6, 3], 1000)

You have to do some basic imports of BasicBlock and Resnet. See the source code of Resnet in the torchvision github repo and you can easily modify the model.