Step to work on a faulty laptop

@josephchristian depends on what kind of work you want to do. First off, you always need to properly identify the motherboard. For example, in your case you only listed a series of laptops. There are many variations and all kinds of different motherboards are a possibility. You always need to know your specific board.

Then you need to identify the BIOS IC. If you want to re-program your BIOS, you will also need to know what type of IC your BIOS is, and you will need a programmer and a "clean" file dump of a working BIOS.

Sometimes you can purchase BIOS IC's that have already been programmed. You would then have to desolder your IC and re-solder the new one.

Now, with all of that said, keep in mind that you should always try a recover your BIOS. Once more for more information on that we will need to know your computers exact model number.

I am sure I forgot something but overall, this is what you are looking at "to work on Bios on the computer".

If this is not what you wanted to know, try to rephrase your question to be more specific.