@Toppress 1/2 I guess this will help you for both your first and second questions. In the post editor screen in the dashboard, if you look around there is an ‘Excerpt’ option box where you add you summary, image links etc. This will help you to control the amount and content of the summary.
3. In the dashboard, you can go to Settings->Reading. There is this option Blog pages show at most. Set the number there and click on ‘Save Changes’. I hope this is what you are asking.
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