All the function keys are not working, right shift key neither.

Does yours qualify for Keyboard Service Program for MacBook, MacBook Air, and MacBook Pro...

https://support.apple.com/keyboard-service-program-for-mac-notebooks

Eligible Models

To identify your computer's model and to see if it is eligible for this program, choose Apple () menu > About This Mac. Eligible models are listed below.

▪ MacBook (Retina, 12-­inch, Early 2015)

▪ MacBook (Retina, 12­-inch, Early 2016)

▪ MacBook (Retina, 12-­inch, 2017)

▪ MacBook Air (Retina, 13-inch, 2018)

▪ MacBook Pro (13­-inch, 2016, Two Thunderbolt 3 Ports)

▪ MacBook Pro (13-­inch, 2017, Two Thunderbolt 3 Ports)

▪ MacBook Pro (13-­inch, 2016, Four Thunderbolt 3 Ports)

▪ MacBook Pro (13-­inch, 2017, Four Thunderbolt 3 Ports)

▪ MacBook Pro (15-­inch, 2016)

▪ MacBook Pro (15-­inch, 2017)

▪ MacBook Pro (13-inch, 2018, Four Thunderbolt 3 Ports)

▪ MacBook Pro (15-­inch, 2018)

▪ MacBook Pro (13-inch, 2019, Four Thunderbolt 3 Ports)

▪ MacBook Pro (15-­inch, 2019)

Note: No other Mac notebook models are part of this program.

https://www.apple.com/support/keyboard-service-program-for-mac-notebooks/

Did you get it fixed?

my shift key makes my screen get smaller and I can't use the symbols above the numbers unless I press the esc key. what happened????

Open Keyboard viewer, what keys highlight in KV when you press them on the KB?