Is there a way to block a user I do not want reading my questions?
All content you post is made available under the terms of CC-BY-SA (this is part of the site's terms of service, see section 3). That means that your posts will be made available for the public to view. You do not have any control over who can view your posts.
You cannot block users from reading your questions.
The underlying issue here (and which may be why you're asking in the first place) is that you're posting questions that are either off topic, not constructive or too localised. This will often lead to them being closed as such.
Please avail yourself of the FAQ and what type of questions are suited for Super User.