configure two server for magento and migirate from server to another

hi
i want to migirate my magento website (2.3.5 version) to new two server
first server for files
second server for database
i want to configure all server for magento... and make sure databases server only connect to files server (not for public)
file server requirement:
- fresh server
- plesk on ubuntu
- varnish
- apache or nginx (what the best for magento)
- Elasticsearch
- optomize server for magento 2

for databases server:
- Query cache
- disable all ports and allow only server files ip

want to move the website with zero error from linode to upcloud... test before going to live