I don't know of any way to change the font. Duolingo considers the font to be part of their branding and does everything they can to force you to see this font. I don't know if font changing extensions or apps might help. As you get more used to the language, you will begin to get a feel for where an I might go and where an l might go and it becomes less of a challenge.
For a hint, two vowels can never be next to eachother so if you see something that looks like II, it must be either Il or lI. In addition, every consonant, with some rare exceptions, must have a vowel on one side (or both - and remembering that tlh is one consonant). So if it looks like an l is part of three consonants in a row, it's probably an I.
jdmcowan 'oH pongwIj'e'. You could also say, pongwIj 'oH jdmcowan'e', but in this unit we only demonstrates it with the name first. The grammar involved is a little complicated and so a full explanation is not given until a later unit. This unit is only intended to give you some phrases you can use right away before we start getting into the details of the grammar.
Since Duolingo has hidden the Tips & Notes I want to make sure you know about them and where to find them. If you have not been reading the Tips & Notes, I would like to ask that you review those.
If you are doing the course on iOS or Android, you cannot currently access the Tips & Notes through the app. To access the Tips & Notes, you will have to access the course using a web browser at https://www.duolingo.com/. You can still do it on your mobile device, but you will have to use the web browser instead of the app (or you can do it from a computer). When you click on a Skill, it will expand to reveal a Start button and a Tips button.
If you click on the Tips button it will reveal the Tips & Notes and give you a detailed explanation of the grammar that is introduced in that Skill. If you have questions after reading the Tips & Notes for any Skills, we are happy to answer your questions, but many of your questions will probably already be answered in the Tips & Notes.
There's three versions for you to listen to. If you still have questions, please ask.
Rather than using two separate words, Klingon uses a suffix which gets tagged onto the noun. It's very similar to if English wrote "my name" as "namemine". Obviously English and Klingon do this very differently, so it can take a lot of getting used to the Klingon method, but once you get used to it, it is clear and easy to understand. pong is a noun which means "name" (there is also a verb "pong", but let's ignore that for now to keep things simple). To say that it is "mine", you add the suffix -wIj. So pongwIj is a single word made of two parts which means, "my name".