I can't sign in my old account and I can't make a new one either

I can't sign out either, I signed in on my xbox 360 before I had an Xbox one, and once I got xbox one, I wanted to stream and I made a new twitch account to match my YouTube channel name and because I have long since forgotten the password of my old one,
but when I got twitch on Xbox one and tried to sign in, I was already somehow signed in on my old one and it wouldn't let me sign out

No, you can't move gamertags to new accounts. You can create new addresses and change the primary account,.

>> My old xbox gamer tag and everything else is under my mother's old email.

If she is still using the address, do not delete it from the account when you create a new one for your own. If you delete it, she will lose it forever.

ETA: you can't move your current address to her account either. You'd need to make a new address.

Hello Harmaa~

I would highly recommend trying to go through the recovery form: Help with the Microsoft account recovery form

Here are also some points that might help you find your Email: Find your Microsoft account email address | Xbox Support

Hope it helps!

Hello dear Gamer, first it's a pleasure to be able to help you today.

My name is Vinicius.

I am a gamer and independent advisor on the XBOX community platform.

Hey Harmaa, how are you today? Hope you're well.

So, unfortunately, there's no way to regain access to your account just by using the gamertag. :/ You would need your email ID, or the phone number associated with that account to do so.

I can't login because It's send a code to my old phone number or my old email address which one is deleted.

So only way if I make a new xbox account?

I can delete this xbox account and make a new with the same email address?