Which OS for VPS to choose?

Question

linux

I want to switch to a more productive machine and a different tariff (plus, geographically closer to the Russian Federation),
but the variety is a little unnerving :)
Now everything works on an ubuntu 16.04 server, theoretically I can switch to 18 - but two main questions confuse
1. If the commands, the location of the directories is radically not the same as on 16.04 then you will have to set everything up again - the gimor is still the same
2. If you take cent-os at all, then you will also have to master the distro in a new way - is it worth it? Maybe in paragraph 2 in general RH choose and work on an adult? Or not worth it?
Everything will work under the Nginx stack, Mssql, ftp, mail - regular web projects / sites

Answer 1

> 1. If the commands, the location of the directories is fundamentally different from the one on 16.04, then you will have to set everything up again - the gimor is still the same
. And what can be "not like that" there? I would choose just 18.04, for the transition from 16.04 - it will be the most painless.
PS
and ftp - why might it be needed in 2020?