Hello @Chiara Spadavecchia ,
In order to achieve that you need to have Jira Adminsitrator access to your Jira instance.
You can then set the permissions the way you want to by creating a specific Permission Scheme and then associating it with your projet.
The following documentation page will probably help you a lot in the process : https://support.atlassian.com/jira-cloud-administration/docs/manage-project-permissions/
Let me know if it helped,
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