You will need to take care of all aspects. The link that @t-p gave you is a must read and just make sure to use strong user credentials for everything, two-factor authentication if possible and security plugins can definitely help.
There are a few plugins that will take care of the basic security measures. iThemes Security is a good one, so is WordFence and Sucuri is considered a solid choice as well. Just make sure you configure them properly.
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