-how does front end look (FAQ, ...)?
-if ticket form is customizable
-how to connect with JIRA ticket system (internal)?
-security (if it's possible to have restrictions per end user?)
-other connections possibilities
Thanks in advance for any support.
A lot of that is a bit too vague to answer directly.
Frankly, your best bet is to simply try it for question 1. Evaluations are available for both Cloud and Server (run it yourself). If you just want a simple look around, try jira.atlassian.com for a brief introduction.
The answers to questions 2 through 5 are "yes, you can". With the caveat that there are loads of different options, and the questions really are too vague for us to give you any detail other than "yes"
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