How to add css and js to Odoo? (Odoo 15 and later)

__manifest__.py

{
    'name':'Your module manifest name'
    'assets': {
        'web.assets_backend': [
            'your_module/static/src/js/your_css.your_css',
            'your_module/static/src/js/your_js.js',
        ],
        'web.assets_common': [
            'your_module/static/src/js/your_css.your_css',
            'your_module/static/src/js/your_js.js',
        ],
        'web.qunit_suite_tests': [
            'your_module/static/src/js/your_css.your_css',
            'your_module/static/src/js/your_js.js',
        ],
    },
}