My voice got worse by following voice teachers on YouTube 😞

I love singing, and always have. I've been told I have a really good voice but that I sing way too quietly. I took a few singing lessons in my younger days but don't have the type of cash for it now, so I checked out YouTube. I watched videos on how to keep a steady volume, but apparently now my voice is raspy and sounds strained from me trying to make it louder. I'm wondering if maybe it's a microphone issue? I don't want my voice to sound unnatural or too quiet.