Congrats @Scott Vogeli! As mentioned above you might be able to get started right away. Here are some steps I would recommend to get started if you're going the "house hack" route (note I'm 4 years and ~30 units in but will start my first hack next year haha! So this what I've done thus far):
1) Where to be: Figure out where to buy your 4 plex. Remember this might not be ideally where you want to be but a balance between where profitable rentals are and a neighborhood good enough for you. Schools / Parks may drive this decision. I was able to get into a smaller town's downtown so got a mix of night life, schools and civics.
2) Financing: Talk to as many banks (conventional, commercial) and mortgage brokers as possible. If you stay with a 4 plex (or fewer units) you can do a lower down payment FHA loan (but maybe higher costs due to PMI). Or if you have money, jump into a 5 plex. Being above 4 plexes frees leners from RESPA / Fannie / Freddie so they can do more interesting things. And if you're looking at 4 units, an extra unit or 2 for 5 / 6 - plexes wont be that more complicated. I initially started with almost all 4 plexes and had a tough time getting financing after my 2nd deal because most lenders wouldn't consider my rental income until I had it for 2 years consistently. Or I had to go to investor friendly lenders who charged meaningfully higher rates or points.
3) Network: Meet as many people as possible. Go to the local BP meet up, go to local REIA meetings. Meet as many landlords and investors as possible bounce ideas off them. Take them out to coffee or lunch.
4) Vendors: Start to build and vet a vendor lists: contractors, plumbers, property managers, lawn service, etc. If you want to look at properties needing work, get a design down that you can do for ALL units so you can buy flooring, vanities, paint, countertops, etc. all in bulk and get volume discounts! (Your contractor or property manager can help with such discounts as well). Contractors will also love you if you have the same design for all units. Additionally, any excess materials, say vinyl flooring, you have from the remodeling, you can use for repairs in the future.
5) Dont mention it to tenants: Prior to having our property manager in place, we never told tenants we were the landlords. We just said we worked for them as managers. This reduces the potential for conflict.
Best of luck!
Suhan