Autoclicker using C++ to click in differnent intervals using RNG * Milliseconds to determine the time between clicks

I've been testing it for hours now and I just can't get it to work. I'm trying to get an Autoclicker to work, using C++. Said Program should be able to click in one certain stop, not specified in the Programm. The mouse only needs to left-click. This has to be done in different intervals. My idea was, that we use a Random Number Generator (RNG) to determine a Number between 1 and 100. This step is easy just using a (rand() % 6) + 1 command. Loading the library you can use the command srand(time(0)) before the for function to actually randomize it. My problem lies after that. How to I get the resulting random number to be multiplied by Milliseconds (preferably also randomized) and then use the resulting time as the time beween mouse outputs?

I know this is much to ask but I'm pretty new to coding and this is a passion project. If anyone would be experienced enough to help me out with my problem it would be greatly appreciated.

Best regards,

Sky