I use Adobe Premiere Pro, but there are plenty of other options out there like Final Cut Pro and Davinci Resolve. As for editing techniques, it depends on the specific needs of your series, but some general tips are to make sure your audio levels are consistent, use transitions to smooth out cuts, and color-correct your footage if necessary.
For sound effects, there are a ton of websites out there where you can find free sound effects online. If you're looking to compress your video to save on file size, you can try using this video compressor online. Hope this helps and good luck with your comic dub!