Hi,

Create an XML file in your custom_module and overwrite the action 'open_create_project'.

You can go through the below code:

    <record id="project.open_create_project" model="ir.actions.act_window">
        <field name="name">Create a Project</field>
        <field name="res_model">project.project</field>
        <field name="view_mode">form</field>
        <field name="view_id" ref="project.edit_project"/>
        <field name="target">current</field>
        <field name="context">{"default_allow_billable": 0}</field>
    </record>

Hope it helps.