According to the ConnectBot issue tracker, it's not possible to retrieve the private key that it created. You'll have to make a new key pair, and share the new public key with tildes. The keys are randomly-generated, so the new pair will be different, regardless of whether you use the same password.

You should do one private key per host. If you want access to something with a key from you phone and computer you should have one key on each. To use ssh from somewhere, from that place to your computer, gitlab, whatever, it needs the private key in the correct place. If it is a shell (like termux) it should be e.g. yoir home folder then .ssh/id_rsa. If its an app, I guess ot tells you(, but I would not give my private key to a random app). To be able to get to somewhere, like from your phone to your computer, your computer needs the public key. The cannonical place to put it is as a single line in a file 'authorized_keys' in the .ssh folder in your home folder.

I'm not sure where ConnectBot stores its keys, so I can't help with the 'transferring to termux' part :-)

What I can tell you is that you should be able to generate and use SSH keys directly in Termux. Here's a quick guide on how to do it: https://gist.github.com/evandrocoan/f503188587587d7b1d1ba8746c9c6107

I've switched phones recently, and I haven't set up my keys yet, but as far as I recall I went through a similar process a few years ago to set up SSH keys on my phone (I haven't tried the steps in that article myself).

I thought title just said sh and not ssh i got really scared

I don't know connectbot, but it's probably not putting the keys where openssh is expecting them.

By default, ssh looks for keys in ~/.ssh/id_rsa(.pub for the public key).

What I would do is just run ssh-keygen from termux, let it create the .ssh folder and set the correct permissions etc., see where it put that folder, and then just replace the id_rsa files with those from connectbot.

ConnectBot is screwed, just use termux, so much easier and stable