You are in luck. Chuck just finished a series on how to do just that. [Set Commercial On]. I am not sure, but it may only be available to paid members. Check it out. If you are not a paid member, now you have even more reasons to become one. I have not watched the series yet. I will wait until I have version 11. However, the membership price has been kept very reasonable and the quality of support is great
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I do not have Version 11 so I can not give you the full details to your question, but the video is there and others will come and help you soon. However, here is what I know that may help you with the more general questions.
You will want to synchronize your video before making your cuts/edits. Otherwise you will have to do the alignment later and that will be much more difficult. Since you likely did not use the Film Clapperboard, or have someone shout "Action", you will have to find a similar type of event to synchronize the movies. Hopefully, once you started to film, you kept all of them rolling continuously. Otherwise you will have to resync at every break.
There are a couple of apps that claim to help you sync your video, but most people just nudge the clip on the timeline until you have a suitable sync.
Regards,
-Vernon