From what I've read so far, one the decision you have to make when interested in lighting work is either going with flashes or studio lights. Can we use both at the same time ?
Yes, you can use wireless triggers, sync cords, optical triggers, etc. to trigger both portable strobes and studio lights. If you are using (preflash) TTL instead of all manual, it will be slightly more difficult. You will have to attach the wireless triggers/sync cords to the controller. Or find optical triggers that ignore preflash.
There may be a difference in color that you should be aware of (e.g. to correct with gels).
It sounds like you're asking strobe/flash vs constant studio lights. It is possible to mix them, but honestly to do so you need pretty powerful studio lights, and pretty weak strobes. Otherwise the amount of light put out by the strobes in the fraction of a second they fire is going to pretty much wash out any light from the studio lights as as to make it pretty much irrelevant as far as the final exposure matters.
Here's a case in point. This is the sooc image:
When I shot that there were two large soft-boxed strobes in front of her (basically I was shooting between them) and a third strobe with a grid overhead and camera right as a hair light.
In the full sized 100% crop of her right eye, you can see the reflection of the soft boxes pretty well, and almost make out the difference in the power levels (one was at 3/4 power, the other about 2/3 if I remember correctly... I had to turn them down so that the weaker strobe over head at full power gave enough light to the hair).
Additionally in the room, there was a fairly bright work light behind and camera left of her, that was our work light so we could see between flashes. You'll note there is no hint of light from that side. In the 1/200th of a second the shutter was open, there wasn't enough light from that source to mater. (f/8, ISO 100 to complete the exposure data.) I looked through my cull pile from the shoot, but I can't find any shots that showed the effect of that light... I suspect the one that would have would be one where the radio popper failed and the strobes didn't fire... but that probably got deleted. What I recall seeing was that her right shoulder had a serious edge light and it cast a shadow onto her neck from her hair. That light would be about as bright as any constant studio lights I've ever seen, and it just didn't compete with the strobes.
Here's the final shot after some TLC in LR:
I am a bit confused with the terms "flashes or studio lights"
Studio light is one light that you use... in a studio.
It can be artificial, either continuous light or strobe (flash) or it can be natural light.
In strobes, you can have monolights normally with a modeling light or you can have portable flashes.
But yes, you can use whatever you want, need, can, have. You can inclusive use bioluminescence if you want.
I must say knowing how to combine them, especially ambient light with strobes, is really interesting.
is either going with flashes or studio lights
You need to see what is the main reason for your light overall.
If you are doing still life photography you can use low power continuous light, but if you are taking photos of people, normally you want to use flashes, that have more power output and the ability to freeze movement because normally people do not stay still good enough to use low powered lights. But with a better sensor, this is changing.