Adding description

[nazlimoghaddam]

Adding descriptions to welcome pages

:ballot_box_with_check: Definition of Done checklist

• [ ] Meaningful title and valuable description in pull request
• [ ] Code change tested manually if not covered by automated tests
• [ ] Pull request linked to one or more issues/stories
• [ ] Acceptance criteria of the linked stories satisfied
• [ ] Code change comprehended by those who approved it
• [ ] State of target branch maintained or improved after the code change