This depends on the settings managed by the group owner or administrator. Under "Group Details - Group Management," the owner/admin can toggle the "New Members Can View History" setting (which is enabled by default):
If the switch is [ON]: After joining, new friends can view all types of history messages from the past 7 days, helping them catch up and join the conversation quickly.
If the switch is [OFF]: New members will not be able to see any chat history from before they joined the group.
⚠️ Re-joining Rule: If a member leaves (or is removed from) a group and then rejoins, the system will treat them as a "new member." Their access to the past 7 days of message history will be determined strictly by the current status of the toggle at the time they re-enter the group.