If you are not a member of any club, you will be able to see all existing clubs by clicking on the new star-shaped shield icon, which is visible in the lower left corner of the platform.
If you know the name of the club, you can use the search engine by typing the name and clicking on the loop. If you do not want to join a particular club, but just want to browse the clubs, you can scroll down or search for clubs by certain criteria by clicking the green filter button in the upper right corner of the window. To see full information about a particular club, click the View button and you will open the club profile.

If you are already a member of a club, you cannot join another club and the icon in the lower left corner of the platform will only lead to the profile of the club you are already a member of. The "Create a club" button will be still visible for you, but if you want to create a new club, you will have to leave the current one.