Magento 2 upgrade and increase speed

1.Project for upgrade :
Update PHP Version from 7.2 to 7.4
Install Elasticsearch 7.x Version
Upgrade from Magento 2.3.5.to Magento (2.4.3)
Upgrade all 13pcs 3th part Magento2 extensions plus install new one
Google Page Speed Optimizer extensions for Magento 2.4.3 from mirasvit.com
Upgrade Porto Ultimate Responsive Magento Theme from 3.2.5 to Version 4.0.1 (07/23/2021)
Settings Activation Porto theme place: Activation is required
Required to keep all custom changes theme and fix each issue after upgrade
to keep live website 7AM - 22 PM ,local time

2.Project Increase speed :
Increase speed check through browser directly webpage test
Increase speed in google page and page load time
Optimize JS, CSS and HTML code structure
Gzip Compression
Optimize Website Media Images
Set Cache Expiry Headers
Integrate Cloud flare Free CDN
Integrate Redis Cache, Varnish cache

3.Project SEO will camming soon

I would prefer to work with an individual rather than an agency
I will share website URL to those who I believe have the credentials to complete the job