Software Engineer in a small firm vs Technical Support Engineer in quite a popular big firm.
Btw I love development. What should I choose and what should be my thought process?

Do what you love.

Avoid technical support in a large company like the plague.

Been there, done that. For literal decades.

In such an environment you are a replaceable cog that will get used until you burn out. There is typically no promotion path to other departments. Your performance will be measured by calls per hour and if you are too slow you will be eventually let go.

Dev at a small firm means more pressure on you directly, but it also means more freedom. You have easy access to decision makers and less organizational cruft that makes getting the data you need harder.

Thanks a lot guys.. I made my decision and I simply can not be the guy who hears clients complaining about their printers not working.