Need help creating a triplet

Hi everyone,

First of all, please let me introduce myself and my problem. This is my first login, but that doesn't mean I haven't done my homework. Before asking the question, I did read very thoroughly the relevant instructions from the handbook, as well as searching for past questions that asked the same thing. After spending several hours trying to figure it out on my own, I had to give up and ask for help.

My desire is to create a measure with two triplets identical to the first measure of line 2 in my attachment. The results I got from working with MuseScore have been chaotic. So, if someone could nicely instruct me the exact steps I need to create that measure, I would be much grateful.