How to quickly prepare an image for a presentation

Hello, I’m looking for a simple method to prepare visuals before integrating them into a presentation or tutorial: cropping, background removal, and clean export in PNG/JPEG, without installing heavyweight software. I tested an online editor that bundles these steps: https://ai-img-editor.com. It’s handy for a quick initial pass, but I’d like to compare with your methods (quality, transparency, and compression). Which settings do you use to keep good readability after resizing? Thanks for your tips.