In order to generate noise signal via Matlab, I would like to suggest you : https://www.mathworks.com/help/dsp/ref/dsp.colorednoise-system-object.html

https://www.mathworks.com/help/comm/ug/random-noise-generators.html

Deep learning Matlab toolbox: https://www.mathworks.com/products/deep-learning.html

To add to the links Muhammad has provided, there is the simple 'normrnd' function that will give you noise samples from a gaussian distribution if that's what you need (https://uk.mathworks.com/help/stats/normrnd.html). You can use it for single samples or provide an array that describes the shape of the output you want (i.e. row / column vector of multiple samples).

sigma = sqrt(18); % standard deviation

mu = 11; % mean

z = randn(100,1); % Sample from Standard Gaussian (mean 0, variance 1)

x = z*sigma + mu; % Sample from Gaussian (mean 11, variance 18)