First of all... kids this age, do not yet have.... fully developed "impulse-control."
And, they have a hard time modulating their voice.
You can teach him how to 'whisper.'
Practice at home.
And, when tired or hungry.... this is not the time to take a Toddler to a venue in which it requires 'quiet.'
When tired or hungry... a Toddler's abilities and patience... is nil.
And, in some venues with a lot of people... Toddlers/babies/kids... get overly stimulated. Hence, they get all tantrum-ey.
A 'tantrum' also, for a young child, it serves to "SHUT-out" external noise and stimuli. It signals... that the child has had enough. And has reached the end of their rope.
And especially... at this age, a child's social skills is NOT yet fully developed either. So, they don't know the parameters of social engagement or not. NOR do they know the appropriateness or inappropriateness of situations. They do NOT have, social skills, mastered, yet.
So, the expectations of him/of a child this age... has to be congruent with the child's age/ability... not the venue.
A child this age ALSO... their "emotions" are not EVEN fully developed, either.
NOR their communication skills.
NOR their understanding of abstract emotions or the requirements of a certain venue.
Kids this age... are not able to sit still and just be quiet.
Your child, IS acting his age.
But the venues... he is in, is not congruent with his age nor his abilities nor his maturity.
He is a Toddler.
Not a 10 year old.