Hello @Nick Gray.
I am currently in residential real estate and have experience with residential sales and residential/multifamily property management. I will try my best to give you the 15,000 foot view of the real estate industry and what some of the jobs/careers are. My thoughts and advice are based on personal experience and what I have learned from reading articles/talking to people.
To quit or not to quit: Before you decide to transition to a full time real estate career you will need to decide if you are okay seeing a significant cut in pay. @Omar Khan is right that the pay will be lower than what you are used to. Real Estate is a fun and sexy industry. Every body talks about it and every body wants to be a part of it. Because of its prestige, how fun it is and how simple people think it is you will have a lot of competition for any job you apply for. If are willing to work hard, network like crazy and accept lower pay for several years you will find great satisfaction (and wealth) in real estate. If you want to keep making lots of money in the short run and continue to invest I would suggest you find another engineering job/company that you enjoy more and save your money. You can always work as an engineer and moonlight as an investor doing your own deals. Once you establish your own track record you will be able to easily find investors for deals and find a full time job in another part of real estate. People love initiative!
Residential or Commercial: Next you will need to decide which path to take. Both have positives or negatives so I suggest you Google (or BP) this question and see what others have to say. If you decide to go commercial I suggest you start in commercial first. Its harder for a residential agent to become a commercial agent than a commercial agent to get started with residential. If you decide to go the commercial route I suggest you move to a large city. You will find more opportunities and types of jobs in bigger cities as well as more networking opportunities.
Category of Real Estate: Next you will have to decide what kind of real estate you want to work with? There are many categories but the big ones are Multifamily/Residential, Office, Industrial, Retail, Land etc. I suggest you read what others have written about it and decide which category to pursue. Choose wisely because once you choose a path it is very hard to switch to another category of real estate.
Types of jobs: Now that we answered the preliminary questions we can now talk about types of careers you can enter into. This is not meant to be an exhaustive list of all the possible careers but is a short list of great entry level jobs I have researched.
1) Analyst: at the end of the day real estate is a financial vehicle that generates cash flow and preserves wealth. Working as an analyst (for loans, development shops etc.) is a great way to learn how to evaluate property and deals. This position will open many doors in commercial real estate and development. It is important to choose an analyst position that matches the category of real estate you want to focus on. Each category of real estate has nuances on how you underwrite a deal and different assumptions you put into the model.
2) Property Management: This is a great field if you are interested in a 9 to 5. The industry is stable, opportunities for employment are quite plentiful and every property in every geographic area needs a good property manager. Working in the management field will teach you a lot about the category of real estate you are managing. You will be exposed to the decision making of both the owners and the tenants. The money in property management is in managing commercial properties (i.e. office, industrial, retail) or really large apartment communities (i.e. 300+ units). Just be aware that it will take a couple of years at an entry level job to get to a property manger role.
3) Assistant to a commercial real estate professional: This is the best way to get a job in commercial real estate! Though you will be working hard with lower pay you will be able to have practical experience in the category of real estate you want to focus on. If you want to get into a competitive field like development this is the best way to gain industry knowledge and contacts.
4) Commercial Real Estate Agent: Though you won't be working 9 to 5 nor will you have a stable paycheck this is a great way to get into real estate as a career. The people you meet, the properties you analyze and the deals you close will set you up for a successful career in real estate! I know two people who started in commercial brokerage and ended up with a 9 to 5 job in commercial real estate. One friend started in brokering multifamily real estate and is now doing corporate real estate for a large retail company. Another friend started brokering retail/office and now is working for a development shop in LA county that buys and rehabs shopping centers. Based on my research I suggest you try to focus on investment brokerage as that will provide the most options.
Before I conclude this long post I want to leave you with three links. The first link is a report from a Florida University outlining the different fields in commercial real estate. The second link is a study on different salaries in real estate. The third link is a brochure by IREM on property management field.
I hope I answered your question and good luck with your goals!
1) Starting a career in Commercial Real Estate: http://www.crossmanco.com/wp-content/themes/crossm...
2) Salaries in Real Estate: http://celassociates.com/prime/wp-content/uploads/...
3) Careers in Property Management: https://www.irem.org/File%20Library/Careers/IREM_c...