Help with Time shifting a discrete signal
yes, you can convolve with $\delta[n - n_o]$ to delay your signal by $n_o$ samples.

I am guessing you know how to represent $\delta[n]$ in MATLAB. And for spreading the signal, you can do by time scaling as $x_{spread}[n] = x[\frac{n}{M}]$. So, basically, the overall operation becomes:$$x_{final}[n] = x[\frac{n}{M} - n_o]$$

In MATLAB you can simulate this by following code:

x = sin(2*pi*(0:0.01:1));
y = sin(2*pi*(0-0.1:0.005:1-0.1));
plot(x);hold on;plot(y);


Here, time-spread is by a factor of $2$ after shifting the signal by $10$ samples.