Each output of the linear layer will be created by the corresponding row of the weight matrix.
I.e.:
lin = nn.Linear(10, 20)
x = torch.randn(2, 10)

out = lin(x)

would yield an output of [batch_size=2, 20] and each of the 20 output values is calculated via:
i = 10
out0 = torch.matmul(x, lin.weight[i:i+1, :].T) + lin.bias[i]

for the ith output.