Struggling with Responsive Design

So I’m trying to make my site responsive for mobile and tablet but I keep running into issues with the layout breaking, especially the images and text not scaling right. I’m using CSS media queries and flexbox but it feels like no matter what I do, something still looks off on different devices. Anyone got tips or tools that can help me figure this out? Like do I need to rethink my approach or is there a specific technique that works better for you? Any advice would be awesome.