Ports used and changing them


I am thinking about installing NextCloud on my home server (windows). Before I go ahead I wanted to check what ports are used and if it is easy / possible to change them?

I am currently using ports 21, 25, 80, 443 and would not be able to change these. So if I am going to go ahead with installing NextCloud I would like to use different ports and still be able to access the NextCloud server from the internet.

I have had a look through the docs and forum but couldn’t fine what I was after.

Thanks for any help Dave

Surley someone can easly asnwer this?

ususally the ports are configured by the (listening) server-software; eg you can configure your webserver-software to listen on port 12345; your ftp-server-software to listen on 23456 etc.
if you want client-software to reach your webserver listening on port 12345, you ususally have pass the portnumber in the URL; eg https://unconventional.webserver:12345
OTOH it’s possible to run different web-applications on the same webserver on standard ports - you could set up virtual hosts or different URLS.

Great thank you.