Just thought I would echo this.
I got my last two completely trained in 2 weeks.
Every 20-30 minutes take them outside. It's a killer but it does work. If they don't do anything, bring them back inside! Best also do it after a long drink or playtime and after a nap. I gave mine a slither of chicken every time they performed outside and tacked on the cue. So, when they did a wee I'd say 'Wee-wee' and hand them some chicken. Same for if they did a poo!
Within a few days they started asking to go outside. If they didn't perform, they didn't get anything.
It's also useful to train them to do it on command so if you're ever on a long journey you can give them the command they know to perform instead of you ambling about the M25 service station with them for 30+ minutes.
I would also strongly recommend a 'house-line'. I used them on my last two and they are a game-changer. They're about five meters long and thin, but you just clip it to their collar (also gets them used to a leash) and you can use it to stop them getting up to mischief in the house/garden whilst still giving them some freedom.
If you have a spare 10-15 minutes, I'd recommend https://www.youtube.com/@McCannDogs/videos
Lots of what they teach is so obvious, but actually watching it can be very helpful (even for someone like me who's had dogs for years)!
It is completely normal to feel overwhelmed @JaneIves! Even I felt like that with my last puppy (still technically a puppy...) and I've had dogs my whole life!