As a mining student, how should we plan in advance? what practical skills or relevant certificates we need to prepare?

There are no certificates required (apart from your degree) that will help your application process. As skills to have, there is no hard and fast rule. Being able to display the ability to learn software or pick up new practices and how agile you are in a constantly changing environment is an excellent skill to posses. If I have to pick a skill to set myself ahead, it would be the data processing skills you don't get taught in a mining engineering degree, like high-level excel or R.

One important skill i've noticed many professionals require is soft skills. The ability to communicate with a variety of people and personalities is critical to get a quality result. By having the qualification you have a baseline set of professional skills however you don't have all the answers. It is the professional who seeks out alternatives from the people who do the work that gets the best result. The ability to liase with mining workforce and other departments to seek out solutions is really important. By giving the crew doing the work some buy in to the process gives them ownership and often a better result. The more you seek out from other engineers and mining crew the better your skills will be. Take advantage of any opportunity to do vacation work and onsite exposure over doing a specific course. The real world exposure cements your knowledge and introduces you to the environment you will be working in.