Virus on my computer and infected internet. PLEASE HELP!?

I'm 14 but im sure i put this virus on our computer. i might know where the virus is from but its embaring and bad. every 5 minutes the same things pop up and i dont know what to do. it says all the programs are infected so i cant access the internet. im using our second computer to say this. I'm really scared. I've gotten in trouble for getting viruses on our computer and its NOT fun. I cant download anything because the internet is infected. everything is infected. im trying to avoid telling anyone because everyone already blames me for everything. i dont want anyone to know what i was doing because theyll be disappointed in me. i just asked this question once but im trying to get as much info. my dads good with computers but im afraid hell delete everything on our computer and hell get really angry with me. i feel really bad and im really scaared. idk what to do. PLEASE HELP!!!!!!!!!!!!!!!!