Raising money?

I've been reading posts from this page for a while. Everybody talks of "raising money". How do you raise money? Some of you might think that's a stupid question but I'm really perplexed. Is this like getting investors? Also why the astronomically high amount of money? I'd need 100k€ max to start my business (game dev studio in Europe), that's why I'd like to know more about it please and thanks for the answers.