dont know password for unlock login keyring or for updates cant update

when i log onto ubuntu OSi get a window that says enter password to unlock login keyring. every password ive ever used dont work. also trying to update it says enter password or keyring? to authenticate cant be done no help in the help section on these matters it says there are no matches to that search i would like to enjoy my computer but instead for the last month all i do is work trying to enter into an os that works sick and tired of it fix fix fix i can not do what i want to do help section is very very vague and incomplete. i know you are busy fixing many bugs and if i sound bitter i apologise but it gets to point where you just wanna smash everything. thank you for your time and hopefully help fixing these matters for me. keep on tweaking!