I tried to switch my dimmer switch to a basic light switch, and when I puller the dimmer off there were 3 black wires, the ground & the white wires were all together with a wire but around them, how so I install the basic switch with this many wires and where do I put them

Please clarify - is the existing dimmer a 3-way switch? In other words, is the light fixture controlled by the dimmer plus another wall switch? And please clarify what you mean by this: "the ground & the white wires were all together with a wire but around them" - do you mean that the ground (i.e. a bare wire) and white wires are connected together?? And how are the 3 black wires connected?

" 3 black wires, the ground & the white wires were all together with a wire but around them" OK this does not make sense to be, please reread it and then rewrite what you see.

Sorry I didn't proof read, I have 3 blacks wires that were connected to the dimmer switch and then 3 white wires that were joined together by a wire nut, and then the ground. Every other time I have switched a light switch I've only had 1 of each. I just want to put a basic light switch on it, not a dimmer switch

Did all 3 blacks connect to the switch? If so it was improper, there should have been a single pig going from the 3 to the switch. The green or bare ground goes to the green screw on the top corner of the switch. There should be no white going to the switch but I suspect the old switch was wired by someone with little electrical skill, certainly no training. If the white did go to the old switch then connect to one side screw of the switch, wrong as it is it is what it is.

All 3 black did go to the switch, and none of the white did, they were just connected together by a wire nut and not touching the switch. The problem is I don't know what to do with the 3 black wires now, do I connect all 3 to the new light switch, so I would have to buy something to connect them before I put them on the new switch. The new switch is just a basic on/ of switch with no dimmer, had the 2 screws to attach the wires & a spot to put the ground

All 3 black did go to the switch,

Are you saying that all three blacks connected to the same terminal of the dimmer? What was connected to the other terminal of the dimmer? Assuming the dimmer has two terminals, at least one of those blacks must have gone to one terminal and the two other blacks to the other terminal - right? If so, you simply need to wire the two terminals of the new switch the same way the two terminals of the old switch were connected. However, if the dimmer had three terminals it will be a different storry ...