Limiting Content on Main Page Including Images: Set Pixel Ammount?

Hi Guys. New to wordpress here, and I’m sure this is a simple fix, but quite simply, I want to not only limit the number of character posts, but also the post length in pixels if possible? Basically, I have posts that contain long threads of images, and I don’t want all of the images to show up in the main feed. Maybe the first few lines of text and the first image? You can see at https://www.digitallush.com what I’m talking about. I reckon this may even be a simple styling fix, but any help would be appreciated. I am by no means a developer but do feel comfortable hacking my way through. Once again, any help would be very much appreciated.

Thank you!