do you mean sampling from normal distribution with new mean and std, then we could use,
normal_dist = torch.distributions.Normal(loc=torch.tensor([0.]), scale=torch.tensor([1.0]))

replace torch.tensor([0.]) with mean value, and torch.tensor([1.0]) with std value
one example would be
x = nn.Linear(3, 3)
t = normal_dist.sample((x.weight.view(-1).size())).reshape(x.weight.size())
with torch.no_grad():
  x.weight.add_(t)