Draw a distribution diagram!

Octave, 34 32 bytes

@(a,b,n)hist(--a+randi(b-a,n,1))

Doesn't work on TIO, but works on Octave-online.net.

It creates a histogram (bar chart) looking like this:

I'd say that counts as "Any convenient format".

If non-zero bins must be shown, then this can be solved in 38 bytes:

@(a,b,n)hist(--a+randi(b-a,n,1),a+1:b)

R, 36 bytes

function(a,b,n)stem(sample(a:b,n,T))

Try it online!

Sigh. A stemplot.

The bane of existence for second year university students taking Introduction to Statistics for [This Specific Area of Study] from some professor who doesn't know what they're talking about but still think stemplots are a good idea because it's still in the 14th edition of the textbook they've been using since the 4th edition was published in 1983.

Charcoal, 25 bytes

≔…·θηθ≔Ｅζ‽θηＥθ№ηι↖←Ｅ⮌θ⮌Ｉι

Try it online! Explanation:

≔…·θηθ

Create an inclusive range of the distribution.

≔Ｅζ‽θη

Sample the range the desired number of times.

Ｅθ№ηι

Count and print the number of each of the range in the sample.

↖←Ｅ⮌θ⮌Ｉι

Print the labels.