Basic
1. Merge css and js.
By Run below command you can find out which mode is active.
php bin/magento deploy:mode:show
On Developer mode
go to Stores > Configuration > Advanced > Developer
Merge css file
Minify css file
On Production mode
php bin/magento config:set dev/css/merge_css_files 1
php bin/magento config:set dev/css/minify_files 1
Js merge
php bin/magento config:set dev/js/merge_files 1
php bin/magento config:set dev/js/minify_files 1
rm -rf pub/static/frontend/
php bin/magento setup:static-content:deploy -f
2. Enable Cache.
php bin/magento cache:status
php bin/magento cache:enable
php bin/magento cache:disable
Advace
3. Configure Radis Cache.
4. Configure Varnish Cache.
5. Configure CDN.
Additional Advace
6. Implement Cloudflare.
7. Load balancer.
8. Containerise.
Code Base
9. Implement lazy load.