As a Twitch streamer, can I then download my saved stream and cut it into individual pieces for YT?

I'm thinking about doing some kind of live LP (like Gronkh if you know him) on Twitch.

That means I'm streaming the game and commenting on it in the stream. As soon as the stream is finished, it is saved as VoD in the video manager.

can I then download this stream and cut parts in the editing program in about 30 minutes?

Would be extremely practical because I would not let the recording run while I was streaming, which puts a lot more stress on the PC. And after all, you want the best performance for the stream.

If you record while streaming you can do that. In principle it is the same as when you first stream and then download the VoD with a tool.

But doesn't that burden the PC too much that it jerks or gets stuck during the stream? I have a good PC but I don't want the stream to lag or the videos jerky during the recording

You'd have to test that. I don't know what your PC can do.

Processor:

Intel (R) Core (TM) i7-10700F CPU @ 2.90GHz, 2904 MHz, 8 core (s), 16 logical processor (s)

GraKa: NVIDIA GeForce RTX 2070 SUPER 8GB OC

RAM: 32GB DDR4 RAM

SSD: SAMSUNG SSD 981 512GB, M.2

HDD: 3TB HDD

That should be enough.