Hi, I have never done any speedruns before but I want to give it a try, any help with the following is welcomed.

how do I get LiveSplit to work with in game time?

do I need to show all time? (real time, in game time, with loads, without loads)

what are some tips for getting started?

Livesplit is usually just used for RTA. That’s probably all you need, as I think most Pokémon games use RTA timing now. Note that in the vast majority of cases, Livesplit isn’t required for verification; mods will use the video to retime your run.

I'm referring to speedrunning in general as I'm still thinking what game I want to speedrun

Check the rules for whatever game you want to run to see what method of timing is required. If you still aren’t sure, make a forum post in that game’s forum to clarify.