Align text on home page

I’m still very new to WordPress and am having a hard time finding anything that actually makes changes to this theme (Invisible Assassin). It also seems like the theme isn’t built similarly to other theme in that all of the other advice for other themes I can’t find that text in my .php files to make the changes I need.

I’m wanting to left align my text on the home page – it’s currently indenting on both posts. I also want to limit the image size of the featured image so that they all end up being the same size on the home page. I’m sure I need to upload my .php files but also not sure how to do that.

Thanks to anyone that can help!

dearheadmeetheart.com