Verified answer

I have translated the original Japanese sentence both naturally and accurately rather than stick to an awkward, literal translation.

まんがでも文学（ぶんがく）でも、その人（ひと）にとって、

理解（りかい）しやすく、覚（おぼ）えやすいのが、よい方法（ほうほう）だ。

"You would be well advised to find an effective and accessible learning method to you, whether it be manga or literature."

In this particular instance, the noun + でも form is used to name/enumerate a few examples.

まんがでも文学でも ＝ (whether it be manga or literature)

でも (demo) is contracted form of であっても (deattemo)

まんがでも文学でも ＝ まんがであっても文学であっても

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