Custom forms created through application composer displaying all projects created by other PM's ?

Summary:

Hi Experts,

Need your guidance,

We are created custom objects like project closure, project risk register, project chacter and lession learn using application composer.

And we customized, "Custom Object Administrator " role and assigning this role to all project managers, this role will allow them to update, delete and edit data in custom forms.

Issue :- We want custom forms to display only the list of projects, where they are PM's. Currently custom forms are showing all the list of projects created by other PM's as well.

How to restrict custom forms to display only projects created or where they are PM's ?