Stuck in login screen after using Migration Assistant

Recently got a new iMac, and the data transfer from my old MacBook Air (still in use) to the new iMac went smoothly using Migration Assistant.

So now I have been doing some stuff on the new iMac and wanted the old Mac to also have the same apps and files that I have installed in the iMac. So I used Migration Assistant to do that and only chose transfer files, documents, and apps. But now that I'm trying to log into my MacBook, first I have to give a password to unlock the Macintosh HD disk, and then it takes me to the login screen, and I type in the correct password, but it just blacks out, and the same thing happens in a loop.

Is this happening because of storage issues? I tried a lot of things to fix this but won't work, for example, I can't get access to safe mode.