Photoshop Page

I use photoshop to create my thumbnails and at the moment I use two different photoshopping software. One is called Photopea and another is called Canva. What I do is I cut out everything and use different effects in photopea but what happens is when I export it, the file is to big for youtube thumbnails so I screenshot the photopea image like this

And then put it into Canva a good photoshopping software and crop it down so you can only see the image and then I export it and it is small enough for a youtube thumbnail.