Because kleki doesn't have a lasso tool, you can duplicate/copy the layer and erase some parts of it (the part you don't want to resize) go back to the og layer (you should lower both of the opacity on the layers, so you could see it better) and erase the part you want to resize, then you should have two separate layers, one with the part you want to resize. you can go to <edit> and use any of those, transform is probably the best one to use. (hope this helps!)
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