Many languages have an "alphabet" set that has some characters that are different than the standard English language set of 26 letters and a number of symbols. Genealogists need to be aware of and use the character sets for the languages of the countries where they are doing research. The best practice in today's world is for these researchers make their entries in their family tree using the correct set that reflects the time and place where their ancestors lived.
I am always surprised when those attending a class I am teaching are surprised that there are computer programs that allow typing on alternative character keyboards. The standard English ASCII Character set, used by almost every English language computer system, contains 128 characters. Here is a screenshot of the list.
The screenshot at the beginning of this post illustrates a configuration for using a standard keyboard layout with Hebrew characters. Most keyboard sets can be expanded by using some of the keys for switching to alternative letters, i.e. shift, control or command, shift-option etc. Of course, if we move to an alternative keyboard, we usually lose our ability to "touch type" and are reduced to hunting and picking out the letters one by one.
Thinking that there is only one keyboard layout is really parochial. For example, here is a German language layout.
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This option is usually found in the preference or setup section of your system. You can do a Google search for specific instructions. Unfortunately, changing the character set does not change the hardware keyboard symbols so you have to have a reference either on the screen or printed out to find the characters you need. If you happen to live in a country where English is not the predominant language, you can probably purchase a keyboard that reflects your character set. (You might notice that I needed to charge my keyboard. I plugged it in and fixed that when I saw the level.)
If you are working online, you can bring up a program that provides an alternative "virtual" keyboard that will let you type with your cursor on the screen. One easily used such set of keyboards is part of Google Translate. Here is a screenshot of the program showing the keyboard for German.
There are a number of other options available online also. But you need to be specific in your online searches since the term "keyboard" is also used for music and other topics. I suggest searching for "custom on screen keyboard" and including the target language.