How i can speed up editing in Lightroom (cloud version)

Interestingly, 4k video is much less demanding of your internet connection than you would think. Typical 4k video is only 25 Mbits/s or so. A typical raw file is more like 50 megabytes nowadays. On a typical 100 Mbit/s connection, it takes at least 4 seconds to download that raw file. Typically when you are working with images in full screen view, it will download also the smart preview, so add at least another second. Oftentimes, Lightroom will only decide to download the raw image after you make a change like applying a preset (or even just previewing a preset). So switching between images will take several seconds if the image is not cached locally. This should be faster if you have already recently done something to the image. A few seconds doen't sound like much but it will really add to it feeling like molasses. Lastly, if you are at the same time uploading images and your connection is assymetric like typical cable internet connections (i.e. 100 Mbit/s down/10 up), it will take even longer to upload the images and when this is happening (the upload being saturated), typically, the download will slow down tremendously so it can get even worse. For a really fast Lightroom cloudy experience when editing raw files from modern cameras, I think you probably need a good symmetric fiber connection (i.e. 500 Mbit or higher both ways).  Slower connections than that and you will often have to be patient. Not unworkably slow but something to realize will be a limitation.