Improve Linux Server Speed. Website are running slow.

Hello. I have a problem with my server speed. Websites run slow on it. It's a really strong server but it's running slow. I think it could have to do with my memory settings.

Speed test says: Reduce initial server response time.

https://gtmetrix.com/reports/www.wqkeglobal.com/2p7IXDk2/


I'm looking for someone to optimize my server for speed and fix any errors that cause websites to crash.


SERVER DETAILS

Operating System: CentOS 6 64bit
Server Architecture: Linux 4.19.0-6-amd64 x86_64
Web Server:   Apache/2
PHP Version:  8.0.26 (Supports 64bit values)
Client Version     mysqlnd 8.0.26

16 XEON cores
16GB DDR4 RAM
Raid 500GB SSD 2TB
200MBIT bandwidth