Hi @Skyhooker,
you must edit the memory_limit, post_max_size and upload_max_filesize directives in the php.ini from the sapi which is talking to your webserver.
Here I described all the relevant values:
You did not mention the sapi your server is using but it is either /etc/php/8.0/apache2/php.ini (for libapache2-mod-php) or /etc/php/8.0/fpm/php.ini (for php-fpm) where you must edit this directives.
32-bit Linux operating systems have certain addressing and file size limitations. A 32-bit system can theoretically only address 2^32 bytes (4 GB) of memory. This means that each individual application, including the operating system itself, can only access a maximum of 4GB of RAM.
There is a similar limitation regarding file sizes. The file system used on a 32-bit Linux system can typically only handle files with a maximum size of 4GB. This is due to the 32-bit addressing, which points to a maximum number of 2^32, which is 4GB.
LFS (Large File Support) allows 32-bit kernels to support files larger than 2GB (often up to 4TB). This was made possible by using 64-bit file operations, even though the kernel itself is 32-bit.
The LFS feature has been incorporated into many modern 32-bit Unix-like operating systems to overcome file size limitations.
So your limitations are not because of the 32-bit Linux.
Much luck,
ernolf