@BoxerTheDog Well that depends. There are books that take you step by step through the process including practice sheets where you start by trying to replicate basic shapes and as you master each part you move on to combining them in different ways or introducing new skills. If you want to be a proper scribe who can replicate scripts nearly perfectly then this is the way they recommend you learn.

For me, I'm not really going for that level of perfection. As long as I see my handwriting get cleaner and prettier over time I am happy with my progress. Typically as I write I can see my errors, they stand out on the page. I also tend to write with an exemplar in front of me if I'm practicing that has a nice zoomed in demonstration of the ideal letter forms of a particular script.. I just just practice the same letters over and over again each time trying to improve on the mistakes of the last one. Over time you improve.

Usually in my writing I have specific letters in specific scripts that dont quite look right (for example my upper case B in copperplate right now). I will often just pick the letter I struggle the most with and focus on that for an hour sometimes.