Create a forum

Choosing and installing a forum engine: There are many engines for creating forums, such as IPB (Invision Power Board) or vBulletin, Flarum, XenForo
Technical specifications (TS) for creating a forum,

1. Forum engine

1.1. Main functions
User registration and authorization.
User profiles (avatar, signature, access level).
Structure of sections and topics.
Moderation system (ban, post deletion, warnings).
Private messages between users.
Support for attachments (files).
Ratings/likes for comments.
Advanced search on the forum.
1.2. Design and UX
Light and dark theme.
Convenient navigation.
Responsive design for mobile devices.
1.3. Additional features
API for integration with other services.
Support for Markdown or BBCode for text formatting.
Database backup.
Technical specifications (TS) for forum functionality
2. General requirements
The forum must be accessible via web browsers on PCs and mobile devices.
Support for multilingualism 
Responsive design and convenient navigation.
Protection against spam and bots.
Possibility of integration with other services (Discord, Telegram, API).
2.1 User functionality
2.2. Registration and authorization
Registration via e-mail, Google, Discord.
Email confirmation.
Password recovery via e-mail.
Two-factor authentication (optional).
2.2. User profile
Avatar.
Signature under messages.
Biography / status.
Activity counters (number of posts, reputation level).
Notification settings.
2.3. Role and access rights system
Administrator: full access, user and forum management.
Moderator: editing/deleting posts, banning users.
User: creating topics, comments, rating content.
Guest: viewing limited content.
3. Forum functionality
3.1. Categories and topics
Category tree (main sections, subdivisions).
Ability to pin important topics.
Closing topics by moderators.
Filters by popularity, activity, novelty.
3.2. Messages (posts)
Text formatting (BBCode, Markdown, WYSIWYG editor).
Adding images, files, videos.
Quoting, mentioning 
Voting (polls).
Editing and deleting messages.
3.3. Ratings and reputation
Likes or ratings for posts.
Reputation system (ranks, trust levels).
3.4. Search
Search by topic titles, post text, users.
Filters by date, author, section.
3.5. Private messages
Personal chat between users.
Group conversations.
3.6. Notifications
New replies in topics that the user is subscribed to.
Replies to comments, mentions.
Notifications about new messages in personal chats.
4. Administration and moderation
User management panel (ban, role changes, statistics).
Content moderation (deletion, editing, moving).
Anti-spam filters, CAPTCHA.
Logs of moderator and administrator actions.
5. Additional features (optional)
API for integration with bots/external services.
Activity feed (latest updates, popular topics).
Badge/achievement system.
Monetization (donations, subscriptions).
Registration and authorization: Users can register on the forum and log in to participate in discussions.
Creating and managing topics: Ability to create new topics, reply to existing ones, edit and delete their messages.
Messaging system: Users receive notifications about new messages in topics they are subscribed to, as well as about personal messages.
Private messages: Ability to send and receive personal messages between users.
Forum search: The search function allows finding topics and messages by keywords.
Reputation system: Users can rate each other's messages, affecting the reputation of participants.
Chat: Built-in chat for quick communication between community members.
3. Rules and moderation
The forum has a set of rules governing user behavior, including general provisions, recommendations, and disclaimers. Moderation is done post-factum, meaning that messages are published immediately, and their verification occurs later.