I can't add much to what's been written here, but I'll just make a couple of comments from personal experience.

The important thing for any singer, in my view, is to find your key in which to perform the song. Check the song's range from lowest to highest note and then find a key which matches that range with your vocal range. I've lost count of the times I've heard singers start off too high or too low and then strain in one register or another.

Be aware that practise at home (say) can be quite different from singing the same song in public. It's easy to sing in a relaxed way - at home, for example - where there's no audience to project to. However, when performing that same song with perhaps greater volume and projection in front of an audience, you may find it's pitched too low. So practise at full volume, regardless of where you are.

Just my 2-penn'orth.