First of all, unless you're a superstar gym bunny, most of us started out being untrained. I know that I started out uncoordinated, very low strength, and I still struggle with my flexibility, as well as a few other things. It's sort of part of the journey we go on!
Strength comes with time and effort. Veena's lessons are great, she starts off slow, so that if you are less experienced or less active, she'll get you going in a way that is totally manageable, while also pushing you just that little bit to help you gain strength. Jamilla's Art of Pole series goes a little further... I believe there's a reason for her impressive musculature, and it is probably the amount of training she does. She kicked my butt, and... well, I'll be going back to it soon! I'm really looking forward to pushing myself.
And I hate lifting weights, going to the gym, etc. Closest I get to a "gym" is my climbing gym, where I go and climb walls and make my hands grip things they don't think they can, push my legs harder, and work on some upper body strength (but, with the right technique, you don't need much at my level).
Flexibility is more or less the same. You work for it, it takes time. Some people work toward the splits for years before achieving them. I've been working consistently for them for over a month, and seeing some vague improvement. I think I'm reaching a plateau, but that's okay. I'll get there! Just be aware that, like strength training, flexibility training is very tough on your muscles- you should never cause yourself real pain from doing it, and you need to take rest days.
Finally, I think you need to look at this from a different angle. Saying "I'm weak and inflexible" may be somewhat true, but it's more like... you've got improvement to make, and you want to make it. Rather than looking at what is behind you, look at what you want to put in front of you, put it there, and make it happen. Believing you can learn something is the biggest step. We all start out in ignorance, or in this case, uncoordinated and weak and inflexible, and work our way toward knowledgeable, graceful, strong and flexible. Everyone has their own journey to take, and you might surprise yourself!