How to access files of my First Ubuntu from my Second Ubuntu

Edit: Ubuntu version is 20.04 LTS

Sorry for the bad Title, I don't know actually how to say it or what terms to use .

So I broke my ubuntu while just playing around. I was unable to boot.

Then I installed Ubuntu in side of previous Ubuntu by making another partition in my hard drive.

So my main Question is How can I use my newly installed Ubuntu to access files in my previous Ubuntu. When I tried opening that home folder it was showing empty. Because other users don't have permission to access files.

How can I give myself permission to access and edit files.

I can login in my first Ubuntu using CLI.

Please help me

Edit: I have two Ubuntus 20.04 LTS installed in same hard drive in different partition, just like people use windows and linux side by side together.

If you can determine the partition number using lsblk you could mount the drive and directly access it there. Example:

$ lsblk
NAME        MAJ:MIN RM   SIZE RO TYPE MOUNTPOINT
sda         259:0    0 476.9G  0 disk 
├─sda1      259:1    0   512M  0 part /boot/efi
└─sda2      259:2    0 476.4G  0 part
└─sda3      259:3    0 476.4G  0 part /
$ udisksctl mount -b /dev/sda2

In this (hypothetical) example, sda2 is a partition that currently is not mounted. It could thus be your system partition of the previous Ubuntu installation. Partitions on internal drives are not automounted, unless they are explicitly configured to be so. This will mount your drive in a folder under /media/<your user name>, so navigating there and clicking the folder where the partition is there will show its contents.

You can also use the the "traditional" mount command, but then you need to be root:

$ sudo mount /dev/sda2 /mnt

This mounts the partition under the /mnt folder.