Torrc ports and multiple onion services

I want to run multiple onion services on one laptop . my questions are… where is the optimal place to keep a separate directory for each onion service? how do i know which ports to use, which ports are available and ideal to use for multiple onion services ? and basically how to configure the torrc file for these needs

Thanks I asked chatgpt “where is the optimal place to keep a separate directory for each Onion service you want to host” and it gave me the answer : Linux (Debian/Ubuntu): /var/lib/tor/ would this work too ?

Also in the torrc file this section is just for location hidden service the part which im supposed to uncomment gives :

#HiddenServiceDir /var/lib/tor/hiddenservice/

#HiddenServicePort 80 127.0.0.1:80

and then

#HiddenServiceDir /var/lib/tor/hiddenservice2/

#HiddenServicePort 80 127.0.0.1:80

#HiddenServicePort 22 127.0.0.1:22

why does it have 2 locations for the second one and not just use 127.0.0.1:81