Quantitative fund strategy orders

Hello, I am a student who wants to get into finance.
I have a question about how the hedge funds put in their orders.
I understand for value funds would call up the market makers and put block trades, but what about quant funds that use computer models to make trades? Do they put orders in the market, just like any other traders? Their orders must be huge, and if they all of a sudden want to short futures contract, wouldn't it move the market substantially due to limited liquidity?

Thanks in advance!