AutoCAD and SolidWorks will serve you well most of the time regardless of industry.
The RMS (Roxar Suite) is generally only useful if you have the foundation or the training to use it. Might I suggest Schlumberger NEXT, they have a lot of training classes available and will give you exposure to ECLIPSE (something like RMS/Tempest). Very expensive, but very respected, they also have intro classes to geophysics and black oil simulation. Reminder, 1 week of classes costs around 4.5k USD.
CFD is generally only covered if you're an instrumentation or piping engineer for OnG. For mechanical engineers if you want to get into the petroleum or black side of things, the best is to start as a production or field engineer. Do it for 2 to 4 years, then get your company to pay for a Masters in petroleum and then move on to reservoir engineering and geophysics.
If you want to be a OnG drilling engineer or mud engineer, my advice is to get your IWCF/IADC BOP Supervisor certification. It is around 3k USD for a 5 day course and lasts 2 years. You should also be fairly healthy and body tough. Start out as a leasehand or righand, move on to assistant driller and then tourpusher/head driller.
If you want to go straight into geophysics ASAP, then start out as LWD, MWD, coring or any other form of logging/geo interpretation. After 2 years they'll start getting you on the modeling tools.
It is a big industry. Tons of ways to go.
the iwcf cert, supervisor level or driller/asst.driller level, which one to start off, i mean since the course for introductory level is hard to find here in malaysia.