Hello, I'm new to speedrunning and I wonder how am I supposed to do Loadless split? I know there is a way to somehow stop timer when You're loading another level but I don't know how. Thanks for help.

You gotta split using livesplit. It has the feature included.
To activate the load time remover, simply right click - > Edit Splits - > Activate.
To show the time without loads while running, you gotta right click - > Compare against - > Game Time

"Edit Splits" --> check if the Autosplitter is On, and also look the settings and make sure that you only have active "automatic start", "automatic reset"
Then for the timer, you need to go to "edit layout" --> and check the "Timer" and change "timing method" to "Game time"
(also make sure you rick click on livesplit and "compare against Game time"

If you want to put a real timer and a game timer, you need to add another timer and set one on "timing method, Game time" and the other to "Real time"
Then try if the time starts when you skip the first cutscene, and if the game time timer, stops on the loading (sand clock) screen.
^^

Thanks for helping guys 😃