All texts that are shows in the page are provide of an translate archive, so you need to get the key on the translate archive and modify in your ‘./src/admin/app’.
Example:
export default {
config: {
locales: ['pt-BR'],
tutorials: false,
notifications: {
releases: false,
},
translations: {
en: {
'app.components.LeftMenu.navbrand.title': 'Dashboard'
},
'pt-BR': {
'app.components.LeftMenu.navbrand.title': 'Painel'
}
},
},
bootstrap() {
},
};
Here you can see how to modify this with detail: Admin panel customization | Strapi Documentation