Is investment in real estate a real investment? In the book The Financial Crisis and the Free Market Cure in chapter 3 author said that investment in real estate is not really investment.

It is jobs that create houses not houses that create jobs

Author motivated it as: when we investing in factories we create new jobs which are producing some goods and after a year we have factory + goods and permanent skilled job place, but investing in real estate (homes) will create only temporary work place (real estate agents, builders etc.) which exists as long as new home is building as far as I understood.
Purchasing new homes would count as an investment. According to Blanchard et al. Macroeconomics: a European Perspective pp 568 in glossary investment is defined:

Investment (I): Purchases of new houses and apartments by people, and purchases of new capital good (machines and plants) by firms.

The source above is the leading undergraduate macroeconomics textbook, so although the definition is not rigorous as it is an undergraduate text the houses are not included just haphazardly without thought. Also note the definition does not include land as correctly stressed in Brian's comment.
However, what the author in that book you cite probably has in mind is capital investment, which is specially investment in assets that will be used as factor of production (e.g. machines, trucks, factory). However, capital investments are not defined in terms of jobs that they create. That is, even investing in fully autonomous robot that would replace worker would be capital investment. This being said when capital and labor are complementary, which is still often the case, capital investment will also create more jobs.
Additionally, in economics when we talk about real variables, e.g. real output, real consumer spending, real investment etc. we mean inflation adjusted as opposed to nominal output, nominal consumer spending and nominal investment etc. that would not be inflation adjusted. So the book you are reading also does not seem to be following economic terminology much.