1st time investor, looking to learn about multi family investing

[Brian Nguah]

Hello, My name is Brian and I am very interested in getting into the real estate investing game. I recently sold my business so I want to start investing the money. I have never done this before nor do I know anything about this. I am interested in buildings with 4-10 units and ideally a down payment of about 50-150k. I want to learn the logistics and mathematics behind purchasing multi family homes just so I make sure I am profitable.

I am also looking to know the business as I want to purchase more buildings in the future. So any books, any gurus or any knowledge I can find online would be greatly appreciated. Thank you in advance.