Hello I once tried to use my skill intimidate on a pc.. He didn’t react to it even though I got some high rolls, I have also had ppl wanting me to roll bluff checks and stuff, when telling a lie..I know some players want both players to agre on using skill points, before they start to roll them. So I would just like to know what you the dm´s think of this.?

Skill use is fine by agreement of both players involved. There is no obligation to roll skills or accept the roll of these skills. They are mostly used for DM events and on some scripted quests.

We mostly just encourage you to play your skills. If you have 0 intimidate, then don't play your character as some menacing monster everyone should fear. If you have high persuade, try to play it. If you have no bluff, try to give signs that you are a bad liar.