Hi Carolina. You would need to add menu security to all other menu items, excluding that user's security group. If this only applies to that one user (for now), you may want to create a security group just for them. You can look at this KB article for instructions on setting up menu security. The important thing to remember about menu security is that if no security groups are selected for a menu item, then security is not enabled for that menu and all users will have access to it.

Create a group 6 for proj mgt and grant access to only that menu.  You will need other groups that have either full menu options or other limited access

see Greig’s link