Studying Engineering at an English-speaking university or on an English-medium course is challenging when English is not your native language. It makes sense to prepare yourself linguistically by learning as much Engineering-focused language as possible before starting your degree course. Certainly, the better you can communicate and understand what your lecturers and fellow students say, the better your results will be.
In addition, the Engineering-specific English referred to above will help them follow lectures and participate in seminars and workshops. So, it is useful to have covered as much as possible before starting an engineering degree. There are many challenges here though, as engineering covers many areas, some of which are very different from each other.
There are quite a few general areas of Engineering English, of course, which would be useful to anyone wanting to study Engineering. These include the language of cause and effect, numbers, dimensions, pressures, temperatures, positions, directions, tolerance, resistance, drawings, charts, common equipment, technology and tools, health and safety, and materials, to name just a few.