First of all, you should find some books about mathematics for self-study and review. It is not easy to learn the knowledge of mathematical modeling well. At the same time, you can ask your own teacher (if you have a teacher) or someone who knows mathematics around you, and solve the problem in time, which is very helpful to increase your self-confidence, or ask for help online and use all the resources that are conducive to learning.

A very good textbook-A book written by Han Chonggeng, Mathematical Modeling Method and Its Application (Second Edition) and Practical Operations Research are two very good books for learning mathematical modeling, both of which can be bought online.

In addition, if you want to learn mathematical modeling well, you need to learn mathematical software, such as matlab, lingo, c++, and you may also need drawing software, such as ps and PS, orange, and it is best to use matlab and lingo.

Among them, a book about matlab published by Tsinghua University is very good, which was written by Mary-"Matlab Mathematical Experiment and Modeling", which is closely combined with mathematical modeling and has strong practicability. Besides this, you can also find other tutorials for learning this software.

Lingo is the best software for solving linear and nonlinear equations. It is very powerful. You can find some tutorials to learn. It is a very practical software in modeling and needs to be studied well.

In addition, C++ programming and ps drawing may be used. Learn solid geometry well when learning architecture. I feel that there should be a goal to make up for it. For example, learn geometry and algebra well, but mathematics is a link, and starting from scratch is not that simple.

Wish you success!