If you have commits in your local branch and you are doing a pull without --rebase you can get merge commits, but I believe those messages should be generated for you(?). I almost always choose rebase over merge so there are no merge commits, all my merges are fast forward. Check your workflow.
Regarding your second question, you want "git add -a". Git gives you the ability to commit "some of what I've changed here", even within files (see git add -i). This facilitates clean commit history by letting you control exactly what is in each commit (even if you changed other files).
And even once you've made your commits to your private branch of course you can continue to change the order of them or combine them with interactive rebase... until you push...
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If you have commits in your local branch and you are doing a pull without --rebase you can get merge commits, but I believe those messages should be generated for you(?). I almost always choose rebase over merge so there are no merge commits, all my merges are fast forward. Check your workflow.
Regarding your second question, you want "git add -a". Git gives you the ability to commit "some of what I've changed here", even within files (see git add -i). This facilitates clean commit history by letting you control exactly what is in each commit (even if you changed other files).
And even once you've made your commits to your private branch of course you can continue to change the order of them or combine them with interactive rebase... until you push...