See Modifying IntelliSense Options. You want "Tools"->"Options"->"Text Editor"->(choose language or All Languages)->uncheck "Auto list members". You can still get statement completion with ctrl-j
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You may also want to read Productivity Tips for Visual Studio.
[The downvotes might be due to people not realizing that asking about software tools commonly used by programmers is in scope for this forum: What topics can I ask about here?.]