Lenni123, welcome to the forum!
It is great that you're asking questions about your cham, so you can keep him healthy.
Kinyonga is correct.
People often worry that the white crust is a problem but it's actually nothing to be worried about.
It does not come from too much calcium in your cham's diet.
Calcium is essential for a young, growing cham especially.
Here is a quote from a veterinarian who is also a chamkeeper and a forum member (Ferretinmyshoes)
"Some reptiles have a salt gland near the nose to get rid of excess salts from their diet or water source. This causes crusty white buildup around the nose sometimes. It is NOT excess calcium (a common myth). The salts are primarily excess sodium or potassium with just the tiniest bit of calcium sometimes. Do not change your calcium supplementation as the buildup is completely harmless and not a cause for concern. Check your water for sodium content and you may need to use distilled water. If the crusts bother you or your cham then gently wipe them away with a moist q-tip. "
The original post is here
https://www.chameleonforums.com/white-substance-nose-78170/
The forum health pages also list this and there it states
"Chameleons have a gland inside their nose to help get rid of excess salts from their diet. Since this gland is just inside the nostril they sneeze forcefully to expel the excess salt secretions so they don’t build up. This can cause a crusty white build-up around the nose. This is generally not a sign of illness if it is the only symptom. Crusts will fall off or can be wiped off with a moist Q-Tip if you desire."
You will find that page here
https://www.chameleonforums.com/care/healthx/head-neck/
There is an excellent section of the forum called Resources which has pages and pages of great cham info.
One that many Veiled owners appreciate is this one
https://www.chameleonforums.com/care/caresheets/veiled/
because it tells you exactly what Veileds need for vitamin dusting and calcium dustings, temperatures, humidity, diet, etc.
There are also links to click on that page for more details about many other important things.
Often people get incomplete or even wrong advice on how to care for their cham and the forum caresheet gives you the info you need before your cham has a problem.
Another way to help your cham, is to copy and paste the questions from here
https://www.chameleonforums.com/how-ask-help-66/and then add all of your answers.
This way, experienced forum members will look over the answers and let you know if there is something important that needs to be changed to prevent your cham from getting sick or hurt..
One thing that often is wrongly told to cham owners is to buy a red light for night.
Chams actually see the light , so they can't sleep and then they get sick.
Again, I'm very glad to see a new cham keeper asking questions.
It's one of the best ways to help your cham to have a long, healthy life with you!