My computer is being very slow and I have a lot of viruses, what should I do?

Well first get an anti-virus program and try cleaning the viruses out.

I've already done that, what else can I do because it didn't work

What AV did you use? What do you mean it didn't work? We can't help you if you don't provide us with details.

One solution would be to do system restore to factory settings. You should have gotten a Recovery disk with the PC or have a Recovery partition on the system that can be used to return to how it was you purchased it. You will then need to run all windows Updates and reinstall all your software.

I used the red blue and yellow

I used the red blue and yellow Red, blue and yellow what?

Um software has names, we have no clue what you are talking about.

Might have to take it to a shop and pay them to do it. It will take a bit more than very basic computer proficiency to unscrew this. If you can't do a system restore. Which in theory should be the easiest option.

If it was me.. I'd zero out the drive... wipe it, then repartition it and reinstall your O/S all using DVD or CD/s as in theory they should be free of any infection. Because there are some nasties out there that will infect the boot sector.

But that's also not a beginners level set of tasks.

My brand new Dell with Windows 10 became infected with adware immediately, probably because I opted out of one or two steps in a very long list of steps to check.
I restored the system. Easy! Not one piece of anti-virus software out there worked, despite saying they did. I wasted days on them.
Adware can be nasty and slow, but I guess it isn't really under 'viruses.'

Also try running malware bytes on your system. It is free. Did you do a boot scan ?