One month of touch typing — what I have I learned

"Have I" is used in questions, while "I have" is used in statements.

On 24th April, exactly a month ago, I accidentally came across the typing technique called touch typing.

The idea is plainsimple — you don't look at your keyboard while typing at all.

I'm not sure if "plain" is used to describe ideas, but if it is, then it's certainly not a common expression. Allow me to suggest "simple". Alternatively: "The idea is plain simple". Here, "plain" isn't used to describe the idea, but rather emphasises its simplicity.

After I haved conducted a small amount of research, I decided to start practicing daily.

(1) "I had"—the past perfect—is expected here, because the research occurred before another past event—the start of your daily practice.
(2) "Small" is not used to describe research. However, it can be used to describe the amount of research.

My objective was to type at the thinking speed and keep my typographicalaccuracy mistakes to a minimum.

typographical: relating to the style, appearance, or production of printed matter.

There is/are a plethora of websites where one can hone one's skills.

Both "is a plethora" and "are a plethora" are acceptable. It boils down to a matter of preference.

After 20 days of incremental learning, I graspmastered/learned the whole alphabet!

"Grasp" is used when referring to one's understanding, such as in the sentence "I could grasp (understand) what was happening in the lecture." It might not be the most appropriate word to use here. You can consider "mastered" or "learned" instead.

With my previous average typing speed being approximately 60 WPM (words per minute) and accuracy 93%, I succeeded to establishin achieving 70 WPM and 97.5%.

The phrase is "succeed in (doing something)".

Although this attainment might seem insignificant and reasons obscure, I had a lot of fun learning!

I'm not sure what "reasons" is referring to. It it referring to your reasons for learning touch typing? Or the reasons said attainment is insignificant, perhaps? It might be good to make this clearer.

Additionally, while delving deeper into the matter, I discovered a plenty of other tools to optimize one's interaction withusage of the computer.

I think "usage" is a better word than "interaction". I'm not sure what it means to optimise an interaction.

For instance, so -called shortcuts.

Even by learning a dozen of suchthem, one can greatly save time in the long term.

One month of touch typing — what I have I learned

The idea is plain/ simple— you don't look at your keyboard while at all.

After I haved conducted a smallbit of research, I decided to start practicing daily.

There isare a plethora of websites where one can hone one's/ their skills.

With my previous average typing speed being approximately 60 WPM (words per minute) and accuracy 93%, I succeeded to establish 70 WPM and 97.5%.

Although this attainment might seem insignificant and reasons obscure, I had a lot of fun learning!

Additionally, while delving deeper into the matter, I discovered a plenty of other tools to optimize one's interaction with the computer.