Yes, they are the two most important aspects in mechanical engineering.
Engineering mechanics is the fundamentals of mechanical engineering. Going forward, they form the basis of strength of materials and theory of machine primarily. Principles of engineering mechanics are also used as fundamental basis of fluid mechanics, thermodynamics and heat transfer. Manufacturing engineering is based upon machine design, which also derives its fundamentals from strength of materials and hence engineering mechanics.
There are many books which explain these subjects in a lucid manner. However, if you have doubt in your understanding of basic mechanics as presented in Class 11-12 Physics course, you should go through them to gain a better understanding. Topics like Newton's laws, friction, etc must be understood before you go in depth into engineering mechanics.
As with all technical topics, practicing problems with increasing difficulty helps in gaining expertise in a subject. Here are some books that you may go through and find the one that is most suitable for your need. Pick up a book and practice the problems, a lot.
Engineering Mechanics: Statics & Dynamics, by Hibbeler.
Engineering Mechanics: Statics & Dynamics, by Meriam & Kraige.
![Mechanics clip 1: Introduction to Statics [EN]](/img/video/mechanics_clip_1_introduction_to_statics.jpg)
Manufacturing engineering is a discipline of engineering dealing with different manufacturing practices and the research and development of processes, machines, tools and equipment. Dealing with machines that turns raw materials to a new product.