My own 2 cents on recording lectures, after recording a ton last year that I will now be re-doing after breaking so many eggs. I'm also interested in any suggestions to improve what I'm doing. 1/

1. Screen capture/recording: https://obsproject.com/ 
This is an open source screen recorder. You can also stream with it. I record at 30 FPS. You can also record sound at the same time (mic and your pc's audio), but now I use something separate for my voice.

2. Voice recording: https://www.audacityteam.org/ 
Open source recording and editing software. So to record, I bring up OBS and Audacity, recording video with the former and audio with the latter.

3. Voice editing.
The reason I do them separately is that Audacity is a lot easier to edit the audio with than with the combined video/audio editing software I'll get to in a second.

And if you want the overall thing to sound good, I think you really do need to take the time to remove little ummms and uhhhs, and to remove background noise and breathing sounds and popping Ts and Ps, to to even out the sound levels. This is all easier/faster with Audacity.

I tend to not use a script, but am starting to see the light on making shorter but scripted videos. Either way, you are going to make mistakes, so when you do, just tap the mic 3 times which will create a visible marker in the audio file so you can find the errors easily.

4. Video editing
I use Lightworks as my video editor. https://www.lwks.com/  I've been able to do whatever I wanted with the free version. You start a project, add the video from OBS and the sound from Audacity.

Because you already edited the sound, you'll need to trim out some of the video using Lightworks so it all matches up. That shouldn't be too hard. You can also add additional text, images, fade in and out, etc. You have to google a bit, but there is lots of help out there.