Typo3 migration/upgrade

Hi,
I am trying to migrate typo3 from a subversion 9 to another subversion in 9.
Shouldnt be complicated but it actually is to me lol.
I couldnt find any tutorials that I could follow easily (what is composer anyways, dont know if I have it).
Basically, i have my files and database. I thought that I should just replace these files

image

with the new ones and upload the database.
Well doesnt seem to be the case.
I wanted to upload the database via phpmyadmin, but need to add the extension but got an error message:
"

Oops, an error occurred!

ERROR: The extension install path “typo3conf/ext/” was no directory!
More information regarding this error might be available online.
"

Seems like its privilege related, but I have all the rights on this folder.

Sorry for the huge post, but I am kind of out of idea for the moment. If someone has a nice simple tutorial, I am all up for. Even a simple guidelines with steps is better than where I am at now.

TIA guys,

Well at least regarding the extension, it seems like its size related in php.
I have set the variable post_max_size to 20M as well as upload_max_filesize to 20M. I have restarted the server using the following command,

systemctl restart php-fpm.service    # typical

But still nothing, cant upload phpmyadmin.

systemctl start mysqld.service
systemctl enable mysqld.service
reboot
These were the right commands for me.

So I was able to load my db.
I just dont understand why after loading the new database I lost the admin tools,

image

Furthermore, I now have this error page when trying to view my website.

image

which directs me to Exception/CMS/1534710048

So far I have uploaded only the db. No files yet. Trying to figure out which files I need to copy over

Ok so the reason I lost the admin tools is because of this new System Maintainer user vs Admin users.
All set now, more info here, https://docs.typo3.org/m/typo3/guide-installation/master/en-us/In-depth/TheInstallTool/Index.html

Back to see which files/ folders need to be copied over. If anyone knows/ has a guideline, I would appreciate.

ok so i almost got it working.
The most important part was to change the baseURL link in the setup file, not sure why it was in 2 different places thought.

My current issues now are, I lost the translated version of the site. I can find it in the backend but for some reason it displays the untranslated version if I click on another language.
Furthermore I lost the ‘last date modified’ footer.
I’m pretty sure it must be a link thats not set up properly.I’m just not sure where to look for now.
Anyone?