20M I want to buy a home in December

Hi all, for starters I'm 20 and I'm looking to purchase my first house soon. I do have a few questions as I'm totally lost as to how to move forward.

I'm hopefully only going to be spending around 100k on the home, hopefully a little less. My area has a relatively cheap COL (rent on average is between 400-700/month to put things in perspective!)

I make around 33k a year until June (in which case my eval comes and I'll get a raise.)

I currently don't have any debt, everything is paid off. I have 3 CCs with a limit of around 11k, with my credit score being around 715. What kind of score should get me a decent rate? (I mean I know the higher the better, but if I stayed at 715, does anyone have any input on what I can expect?)

What all do I need to look for when looming at a home? I know the general consensus is to put 20% down to avoid PMI