Try not to worry. I'm just recovering from tonsil cancer and whilst the side effects of radiotherapy is no joy the survival rate is one of the highest of all cancers.
You'll probably get 7 weeks x 5 days (Mon-Fri, weekends off!) of radiotherapy (10-15 mins & painless), plus a dose of chemo on your first day and one about 5th week in. It's Grade A world class treatment. They'll probably test you for a virus called HPV, which if you have, bizarrely increases your survival rate further.
You'll probably need to arrange lifts after first week or so of treatment, as you'll feel **** for driving. Get a rota in place for people to take you as soon as you get your treatment schedule. Taxis other option if hospital not too far away, wouldnt recommend public transport.
Pre-treatment you'll have a PEG or some other type of feeding tube fitted to your stomach as you'll be living on medical nutrient milshakes for a while as your throat being nuked by high powered X Rays will be "closed for business". Eventually this will be taken out post treatment and you'll wean yourself back on to normal food over a few months, sloppy stuff to start, then more lumpy stuff then tougher stuff to chew and swallow still later (I'm still on semi-solids 4 months after treatment but PEG removed).
1. Don't worry about Radio or Chemo they aren't painful
2. If offered some "sedation" for your PEG fitting, take them (benzos) as it can hurt a bit
3. You'll probably have to a have a few teeth out on the side of your cancer. These are any teeth deemed at risk of future extraction as they can cause problems with your jawbone if extracted after radiotherapy. Restorative denistry is an option, I'm just chewing on one side of my mouth at present.
4. Worst time is last week of radio and the week that follows it. After that you'll gradually start to feel better.
5. Relax, it'll all be fine. They successfully treat up to Stage 4 tonsil cancer and once it's gone it doesnt come back.
Oh, and I lost my wife to suicide early in my treatment (unrelated, Bi Polar depression) so if I can do it, anyone can.