It's probably this itinerary but I don't undestand why it says self-transfer and why he has posted the screenshot of "Self-Transfer"
(which means that you have to collect your bags and check in with another airlines, meaning you have to clear border and security, 1.25h is a bit tight.
No, it's not difficult. If you have managed to get that far in life I'm sure you can do it without speaking a word in thai, I've done it myself with all the info I could find on the web.
To summarize it:
1. Visa: Tourist -> more than 30 days validity
2. Location: Bangkok: -> You need to have had TM30 filled if renting privately. I don't know how that would work with a hotel.
Step 1. Go to immigration (Immigration Division 1, Immigration Chaeng Wathana ) with copy of your address registration and ask to apply for a letter confirming your address for the purpose of obtaining driver's licence. They have this special form.
Pay and wait 14 days.
Step 2. With that letter, go to DTL building 4 (I think) and apply for thai licence with your IDP. You will need to do a few tests, such as colour blind test, reaction time etc.
Don't you have a PDF editor for your bank statements ?
P.S. I don't understand how bank cannot update/fix your name. If that's really the case then get a new bank and normalize your name across everywhere.
P.S.S. What does it even mean "passport name" and "married name". You should have only one legal name. I don't understand how Americans/westerners put random names on documents. e.g. Francois and Frank, Katherine and Kath.
The only exception is if you have a Thai and English name.