new to the biz, looking forward to learning

Hey everyone! My name's Carl, I'm from middle Tennessee. I've been lurking on seversl forums for a while but finally decided to post.
I'm pretty much new to this business, did a little part time work with a local company years ago but was mostly just a mule, carrying equipment and moving furniture etc lol. I'm looking to start from scratch and any advice you can give is greatly appreciated.
While you're here, I'll give some basics of my plan and hopefully some will give advice

I want to be debt free, I don't like credit for personal use and definitely not business. I have about 20k saved up for this venture. I'm thinking about going with either an op system, encap, or hwe truckmount to start, then expand to offering different options.  (advice on which to start with is appreciated)

I'm going to start with the cleaning business being a side job, and keep my current job. I'm a paramedic, and only work 10 days per month (24 hours on, then 48 off). Hopefully I can build the business into my full time gig, and just volunteer as a medic.

I'm looking for residential and commercial jobs, as well as wanting to eventually expand into different types of carpet cleaning and maybe even duct cleaning. I'm also looking a spending some of my start up money on attending some iicrc classes and being certified asap.

Glad to be here, and I'm looking forward to becoming more involved as I learn more.