UI/UX improvments for event creation to ease the creation for first time external users

**Is your feature request related to a problem? Please describe.**

When creating events it can be confusing as to what fields are required to fill and what each tab does.

**Describe the solution you'd like**
A clear and concise description of what you want to happen.

Small information boxes and/or more handheld walk-through on the event creation.

For more walk-trough implementation, each field could be given one-by-one and explained what that field does. This of course would only be for first event creation.

**Additional context**
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The idea behind this feature is the ease the event creation, decrease the number of scheduled demos, and decrease the contacts for the Junction team to support.

Beginne mit der Überprüfung der Benutzeroberfläche zur Ereigniserstellung und konzentriere dich darauf, welche Felder erforderlich sind und welche Funktion die einzelnen Tabs haben. Definiere die Erfahrung von Erstbenutzern und überprüfe, ob Informationsfelder oder eine schrittweise Anleitung während der Erstellung des ersten Ereignisses jedes Feld erklären.

Vom Indexierungsmodell aus dem Issue-Text verfasst.