Confused about recommendation letters?

First off, I’m sorry for the excess of questions, but I am so confused by the entire process. Is there some resource on the internet that explains each and every detail of the entire process?
Here are my questions regarding recommendation letters for the undergraduate application process (in the U.S.):
I’m planning on applying to 10 private colleges; can I ask the same teachers to write letters for all of them? Is there a specific prompt that they have to follow and change up the letter for each university?
Is there a form the teachers need to fill out? Or do they just write whatever they please on a blank document?
Do they send the letters through mail or do I? Can it be sent online?
When are the letters due? At the same time applications are due? If the letter is sent through mail, how will I know it got there on time?
I honestly will probably think of a million more questions to ask, but these are just a few. This entire process has left my mind spinning, and I can’t even figure out the most basic guidelines.
Again, sorry for bombarding y’all with all these questions; thanks in advance for helping me out!

Your teachers should know how to write a letter of recommendation; that’s not your concern. If these colleges are on the Common App, all you need to do is to send them a request through the application and they will get a link to upload their letters. You can send those letters to whatever school that uses the Common App. Otherwise, you have to follow whatever the college’s admissions page says. Some can be submitted online, some may have to be mailed. It depends on the school.

It is also worthwhile to talk to your school GC - they should be able to help regarding specific teachers that you may be considering.

Your guidance counselor should be able to help you but pay attention to which colleges have specific requirements re subject matter teachers for recs. At my students’ school, they identified 2 teachers each for rec letters for all their applications. However, MIT for instance wants a Math or Science teacher (understandably). This got by the college counselor. For Caltech and MIT make sure you pick a Math or Science teacher if your other two letters are non-STEM.

@azzameria definitely check with your guidance department. Our school used Naviance. My son had to ask the teacher in person, then log into Naviance to send the request. The teachers/guidance could see through Naviance all the schools he was applying through and submitted the letters through that. We would also see when the letter was submitted. He applied to 9 schools. He asked 2 teachers who sent letters to all the schools. His guidance counselor also wrote a separate letter.