Bitrix24.Sites has a built-in graphics editor. You can crop an image to fit the block, edit image, apply filters and add effects.
How does it work
Upload an image to a block.
The graphics editor opens automatically. First, you need to crop an image the way you need.
Edit the image. You can apply filters, add text, blur the image, add stickers, etc.
After you've done all the needed modifications, click Apply at the top right corner.