"When we start a new blog page views are important for applying Adsense earnings."
In general, Google never reveal the eligibility for approving AdSense application thus can't exactly say about it, however, some quality, active and useful info must be there on blog to review AdSense application. Yes, the blog also shall be more than few months old beside bloggers active and quality contribution beside his/her profile. Pageview is one of the criteria to review the application, without pageview of the blog, I think Google won't even consider to review for the same.
"In general for a newly started blog how much time it takes to get started page views."
It is all depend on the content of the blog beside whether the blog is of custom domain or free blog etc. In general, like Google, they consider natural traffic for the blog than artificial or social one. The blogger must concentrate to contribute the valuable and quality content on the blog to get the natural (organic traffic) visitors that would help them for pageviews and AdSense approval.
"More number of posts or the time duration of the blog run will decide the page views?"
Both, more number of quality and unique posts and the seniority of the blog will decide the page views. It doesn't mean the less searchable unique and quality post or senior blog with irrelevant content will bring the visitors to blog.
"Is it good to start a blog with one category of posts like jobs, Recipes, Sports, Articles, photos etc. or many categories together in one blog?"
It is always better to start with a blog with just one category.
"What techniques to be improve the page views for a non-technical or lack of SEO knowledge individual?"
It is better to learn 'how to increase page views' articles that are already available online. Follow the simple tips given over there and it is not necessary that one has to have technical knowledge for it. As says, 'content is King' and reaching top 10 or 20 in search engine result is like 'winning the battle'.