What you need to make sure of if you want to transfer your current odoo "install" from one environment with U20.04 to one with U24.04 is the compatibility of the python environments and the packages used. 

You should check what python version is currently used by Odoo 14 on your production env with 

python3 --version

As well as list/freeze all the current packages installed in the python environment and save them in a requirements.txt file (used later)

pip freeze > requirements.txt

Now on the U24.04 environment, you should also check the python version with python3 --version to see if it corresponds to the old one and use 

pip list > packages.txt

It is possible that your python environment on U20.04 is not similar to the one pre-installed on the Azure VM's with U24.04. The goal is to make sure you have the same python version + packages on the destination environment to ensure a smooth transition. It could possibly work with different python versions but the minimum should be to have the same packages (and version).

Once you have the same python version installed on the U24.04 environment, make sure to attribute that version as the one use by the python3 command. 

For example if Odoo 14 is using Python 3.08 on your production, and you have Python 3.13 and Python 3.08 installed on the U24.04, you need to make sure that running the command "python3" on U24.04

python3 --version 

will actually return 3.08 and not 3.13. If this is not the case, you can either create a virtual env that uses the right python version OR by changing the environment variable for python3 globally (recommended if the U24.04 VM is only used for running Odoo 24.04). Either of these solution can be done with pyenv (used to easily managed different python environment with different version if needed) or by changing the environment variable (alias) if you want to used a default python version for the environment of the U24.04 VM or using 

update-alternatives

 Once this is done. You now have the same python versions, you can install pip, then use

pip install -r requirements.txt

to install the same packages that you had on U20.04.

Once this is done, you can transfer you can install Odoo 14 on the U24.04 VM, make sure to transfer/copy any custom Addons in the addons folder, make sure to transfer/copy the odoo.conf file and any other custom files you had on the U20.04 machine to the the U24.04 VMs. 

Then you can export/import the databases (including the assets / static files). As a precaution, I would also ensure that the same postgresql versions are present and used on both machines (although postgresql is more resilient to version change and this should not cause issue unless you would jump several versions of postgresql). Dont forget to check your pg_hba.conf file on U24.04 is configured the one on U20.04 if there specific rules that were setup for Odoo 14 on the production environment. This file is located in 

/etc/postgresql/<version>/main/

Hope this helped,

Best of luck