How to add Resource Pack (Texture pack) to a server:
You need to upload the resource pack to a website with a direct download link (if you give us the file we can load it on our download servers for you - contact support)
Then you paste that link into your server.properties file where it says resource-pack:
Note that the ":" and "=" characters need to be escaped with backslash (\), e.g. http\://stipe.com.au/somepack.zip?someparam\=somevalue
Final outcome should look like this:
resource-pack=http\://stipe.com.au/somepack.zip?someparam\=somevalue