The 90 days is what I was saying that I am allowed to travel to another country under my US Passport. My passport is vaild for 10 years not needed to update it, however I have been told that If I apply for a Visa I would need to surrender my Passport because the visa would take its place.
The visa is essentially a sticker placed IN your passport, not something you travel with IN LIEU OF your passport. You submit your passport with your visa application so that the visa can be placed in your passport.
I've read through some of your posts, and I think I'm a bit confused as to your intent. If you are intending to enter the UK as a visitor, you will likely not need a visa. The US is not a visa national country. If you are concerned that for some reason you may be turned back at immigration rather than allowed into the country, you can certainly apply for a visitor's visa, but your intent must still be to enter the country as a visitor. That means entering for a set amount of time (less than 6 months) and then leaving again. They will be looking for things like a return ticket, proof that you can support yourself w/out taking a job or any public funds, etc. If you are afraid that you might have trouble w/the financial aspect of the visa, you can get a sponsor. Sounds like this is what your friend did...however, it is still a visitor's visa.
If you are intending to settle in the UK, a visitor's visa is not appropriate, and indeed you may still be turned back at immigration even with a valid visitor's visa if the entry control officer thinks your intent is to settle. (It's not likely, but it can happen.) If they believe you are entering the county other than as a visitor, they may search your luggage looking for proof of your true intentions. This can include diaries, correspondence, CV's, etc.
I don't think anyone here is trying to be mean to you, just help you to understand the ins and outs of UK immigration. It is quite complex and can be confusing. They are very strict and there can be many hoops to jump through before you can settle in the UK. Even as a British citizen, I still have to obtain settlement visas for my children before they can live w/me in the UK.
Good luck! Hope you get things figured out and that it all works out for you in the end.