Learning to microsolder is difficult with low quality equipment. If you want to put out a fire, then a firehose with a steady strong stream will make the job easy, where a firehose that puts out fits and starts of water with variable water pressure will be very difficult if you've never done it before.
My YouTube channel iPad Rehab has tons of videos that walk you through my thought process as I diagnose boards in real time and you can listen to my tips on technical proficiency. My advice would be to join a forum, like this one, and solve one problem at a time--ask for help after you've exhausted all other resources and have put considerable thought into the problem and have gotten stuck.
Our Practical Board Repair School is a great way to skip the 6 months-2 years that it can take you to learn microsoldering by trial and error and we often have complete beginners at the course. However, this is an investment and you need to be sure that you'll have the business volume after learning the art of microsoldering and board repair to make it worthwhile to invest in training and tools.