Your question is really many questions in one. It is difficult to provide specific answers but I would suggest a good web site for starters and also that you contact your local Extension Office for more information on plants and landscaping. It may be that they offer some classes or could refer you to Master Gardeners for one on one advice. There may also be tours in the area that visit gardens for ideas and inspiration.
These following web site has good adapted information that can be useful to you:
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