How to upgrade ram of macbook pro 13 inch 2018 from 8 GB to 16 GB

https://everymac.com/systems/apple/macbook_pro/macbook-pro-retina-display-faq/

Remove and reinsert the RAM on the MacBook.

I’m happy to help further over the phone at https://www.6ya.com/expert/michael_195f36f311cb10df

You mean what is the MAX Ram you can out into the system . To up grade. need to know the model number Year it was made . Go to the apple Icon go to About this mac. get the details , And then you can search the web for up grade. You can just take it to apple . but you also on some macs , put the ram in your self and buy ulternitive. Fist need to know what model and year. Most before 2011 to up to 4 After that 8 GB of ram.

Did you try searching before asking? MacBook Pro 13 Unibody Early 2011 Battery Replacement

what are the steps you have done to determine that the MAcBook is defective? It could be your router, network device driver...

Please provide more information.
To what would you like to upgrade it?

Since OSX Mavericks was just announced, I'm going to assume that's what you're wanting to upgrade to.

Not all Macs can run Mavericks.

Mavericks Capable Macs

Mavericks, like its predecessor Mountain Lion, requires one of the following Macs with at least 2 GB of RAM and 8 GB of available hard drive space:

• iMac (Mid 2007 or newer)
• MacBook (Late 2008 Aluminum, or Early 2009 or newer)
• MacBook Air (Late 2008 or newer)
• MacBook Pro (Mid/Late 2007 or newer)
• Mac mini (Early 2009 or newer)
• Mac Pro (Early 2008 or newer)
• Xserve (Early 2009)

If your Mac isn't one of the ones listed above, you won't be able to upgrade.

If you have an iMac, MacBook, MacBook Pro, or Mac mini model that was originally released in Early/Mid 2006, the latest version of Mac OS X your system supports is Snow Leopard.

http://store.apple.com/us/product/MC573/mac-os-x-106-snow-leopard

...

It's a good product but has it's limitation in terms of no CD/DVD drive, lack of USB ports, quite a small hard drive (80 GB as opposed to 500GB for a low end Macbook Pro), less RAM and smaller screen (11.3 inch as opposed to 13 inch for a Macbook Pro). For another 200 dollars you could buy a macbook pro which has higher specs.

4GB is the MAX but only 3GB is utilized.
What Os are you running. Tiger Leopard Snow Leopard?

The earliest MacBook (Pro) models have a limit of 2 GB. To check the specific model, in the Apple menu select about this Mac. Then press more info... . Look at the line like "Model Identifier: MacBook5,2" for my white early 2009 MacBook. If the numbers are 1,1 then for sure you have the oldest model and are memory limited to 2 GB, as the sum of both cards.
That's just like my wife's, it was a Core Duo and not the current Core 2 Duo. Works fine. I was ready to up its memory but read about this in the Apple Support Forum. It came originally with 1 stick of 512 MB, IIRC. I upgraded it to 2x1 GB for a lot more than the 2x2 GB in the newer. BTW some of the Macs between these only take 3 GB but will work with 2x2 GB just throwing 1 GB away. -Ken