Solve your termux repository

Step 1: open terminal

Step 2: type (nano /etc/apt/sources.list ) press enter.

Step 3: type this 👇👇

deb http://http.kali.org/kali kali-rolling main contrib non-free

deb http://http.kali.org/kali kali-rolling main contrib non-free

deb http://http.kali.org/kali kali-last-snapshot main contrib non-free

deb-src http://http.kali.org/kali kali-rolling main contrib non-free

Step 4 : press ctrl+O and press enter

Step 5:press ctrl+X

Now you can install packages without any problem.