An other “simple” edit that seems buried under a bunch of stuff - the first thing people want to do is rotate a video that appears 90 deg off. I tried every intuitive thing, searched for menu options etc and nothing. I then searched here and someone said could be done with “size, position, rotate”. Oddly, that must be for another program besides Shotcut because I have no such option.
Look for a basic Shotcut tutorial on youtube, it’s gonna be way faster than having people directing you in text form. These are all very basic techniques that you will 100% be shown in any tutorial.
To rotate, depends. I assume your entire video is in the wrong orientation, if so, then in the Properties panel (select the clip first) there’s a Rotation field, choose one of the 4 options there (probably 90 or 270) and you should be all good.
If it’s just a section then select it and open the filters panel where you can search for “size, position, rotate”. – Again, this is the most basic thing to do in the program, it should be explained in the first minute of any beginner tutorial.
To cut out: you add your video to the timeline, move playhead and press S (for split) at the start of where you want to cut, then again S at the end, and right click the segment and choose Ripple delete.
As @daniel47 said, that lives under the Filters tab if you’re using that. That same filter can be used to zoom in.
I will also mention this since it might be helpful: If you want to crop stuff from the video (as in remove pixels from the top, bottom, left, or right), you have a few options. The way I usually do it is to use the “Crop: Source” filter. To ensure you have this option, you should select (click on) the clip that you’re cropping (not the track (“V1”, “V2”, etc)). Then, you can select the number of pixels to remove from each edge as well as set a center bias if you don’t want the crop centered (I usually leave the center bias alone and remove the pixels I need to from each edge).
To delete portions of a clip, as @daniel47 mentioned, you can split a clip at multiple places and delete the portion you don’t want (enable “Ripple Delete” if you want to remove the gap that would result). Another tip: If you’re not sure if you’ll need the clip later on, you can move those clips to another video track (click on the menu in the timeline → Track Operations → Add Video Track) and disable the audio and video on that track (toggle the volume and eye icons on that track).
All of this is covered in documentation and/or in tutorials (you can search the tutorial category here if you’re not sure where to start).