I would suggest against turning all the readings to katakana, since as @GreekCupOTea said it is used for specific purposes - loanwords and often denoting onyomi readings next to kunyomi (but i guess onyomi is sort of like a loanword, a loan reading i guess).
It is hard to get enough practice reading, i have a similar issue, but i found the onyomi script suggested by @wojtaso9 quite helpful since it makes your brain think while doing the readings, and it needs to know how to read katakana to check your answers are right. But while giving you the practice it still keeps the distinction and keeps the katakana within a context you’d usually see it. If you’re looking for more vocabulary with katakana, asides from jsut consuming a bunch of readign material, there are flashcard decks of non-kanji vocabulary on most flashcard platforms.
Hope some of that helps : )
Also, since it’s your first time(s) posting:
\textcolor{MediumPurple}{\huge\textsf{Hi}} {\huge\textsf{@RevDecim}} \textcolor{MediumPurple}{\huge\textsf{and}} {\huge\textsf{@wojtaso9}} \textcolor{MediumPurple}{\huge\textsf{!}}

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