Can I use a laser spotter as a guidance to a star in the sky? That's if you're by yourself. Here is an example of a spotter on a tripod 10 feet any from my camera!
It depends on national, state/provincial/territorial, regional, or local jurisdiction. Not knowing where you live (though from your name, I would guess Eastern Europe), I would stay on the safe side and say no, you may not use a laser pointer at night.
For example, in Canada, it is a criminal offense to even merely possess a laser pointer of more than 1 mW (most laser pointers are 5 mW) outside a dwelling in urban areas and within 10 km of airports, and generally even elsewhere — there could be fines of \$1,000 up to \$100,000 (for individuals) and up to 5 years in prison. See Transport Canada’s website for details.
However, members of the Royal Astronomical Society of Canada or Québec’s Federation of Amateur Astronomers may apply for a temporary or permanent permit. I have thus legally pointed a 50 mW laser pointer (about 10 times more powerful than the regular pointer) towards the sky at night with no problem, as I was covered by a permit. There are conditions for obtaining such a permit, and it may be revoked if the person using the laser does not follow certain rules.
This is poor dark sky etiquette. Even when you're "by yourself", the laser is visible from a long way away (miles away sometimes). And you can't possibly know who's doing what in the entire visible area. What makes it even worse is you'll be using it to point at popular targets other people will be using telescopes to look at, increasing the visible range even further.
They are also generally unnecessary, because if you know where an object is well enough to point a laser at it, you can point a telescope at it.