My laptop is having i5 8th gen and ram is 8 gb too...but it has 1.7 GHz processor ,can I increase the it??
Some laptops have overclock-capable CPUs and a BIOS that isn't locked, but these tend to be a distinct minority and given the constraints of cooling and power delivery a laptop has that a desktop doesn't, generally not recommended.
Shorter answer: probably no.
More information, like specific CPU and specific laptop could possibly be helpful, but it probably won't change the answer.
No, but the base core speed is the base speed, most laptop CPUs will go higher than than if needed and if power and temps allow without damage.
Look at the specs of your CPU, you will likely see the base speed and then a second faster speed listed for it.