Do ground level stairs need railing?

[Will Fahmy]

Hello, I just recently acquired my first rental property in Pennsylvania and a friend told me I'm probably going to need to install railing. My first question is do I actually need to install railing on some of or all of these stair cases? If I do need railings installed would it be wiser to get a contractor to install them so they meet code or would someone with very little experience be able to do it?

Front stairs; these look ground level and I heard ground level stairs don't need railings is that true?

Back stairs; these look ground level as well

Front door stairs are not ground level but I don't know if there are enough stairs to require a railing

Any help is appreciated! Thank you!