My team leader has invited me to his Trello and I created a board on it and the visibility is "Team" but my team can't view my board. What seems to be the problem with this?
From the information you've provided it sounds like it should be working for you. Here's a couple of things to try:
If you're in multiple teams, double check this board has been added to the right team. On the main board page at the top next to the board name, check it has the name of your team and says Team Visible. You can click the team or the visibility to change it if required.
Try sending the URL to a team member to see if they can visit the board directly. If so, the permissions are all as they should be, so it might be that it's not showing because they have many other boards listed. If this is the case they could star it, be added as a member to be able to edit it as well, or just search for the name of the board.