Rather depends on what do you mean by 'do some mini-projects' ? Design, build, or manage are the first obvious choices. Then the electronics field is vast, RF, analogue, digital, embedded micro control for main designs, then the interface folks, EMC specialists, network specialists, sat link specialists ... etc.

I have been in it 40 plus years, first as a hobbyist, and for the last 3 and a bit decades  for a living, and having worked as the design authority on a several projects I still would not pretend to know the half of it.

What is your current  skill set, what are your interests, where do you want to go to ?.. If you can narrow it down a bit,  then the question will become easier to answer.

Not intending to scare you off, but trying to help you focus the idea a bit.

Mike.

Hello Mike, 

Thank you for your response. 

I am a graduate with a Bachelors Degree in Electrical & Electronics Engineering. I am working in Fire Alarm Systems Installation company which is no way related to my field. 

I am interested to gain knowledge and expertise in the field of electronics. I need to start from scratch as it has been 8 years since I left the branch. This is why I asked for guidance on where can I start. 

Well, if you feel you need to truly start from scratch (though if you have a degree, I'd be surprised if once you get going you find you really do but it is fair to say that no one will employ you to do electronics on that basis... ), you could do worse than building  a few hobby gadgets, either analogue (something with op amps FETs that sort of thing ) or digital (a quick Arduino sketch do something fun like a push button dice for the kids to play with)

The advantage of hobby things is that no-one is demanding a finished design by Friday or worrying you about the overspend.

If you have not already, master LT spice - its good, quick and free. And used by some  of us professionals too sometimes

In tandem with that try reverse engineering/ repairing some broken items of low value (actually even things like watching the BigClive YouTube videos can be quite good in this regard as a quick refresher of how to do it. .)

Let us now how you get on.

Mike.