Yoga isn't about where you can reach. It's about learning to be present where you are.
You don't need to be flexible, experienced, or able to hold every pose perfectly to begin. Every body is different, and every practice can feel different from one day to the next. The most important thing is to start by paying attention.
Move at a pace that feels right for you. Notice your breath, your balance, and the sensations in your body. Some days you may feel open and energized; on others, slowing down and choosing a simpler variation may be exactly what you need.
There is no need to compare your practice to anyone else's. Yoga is not a performance. It is a personal space to move, breathe, and reconnect with yourself.
Start with what you have. Use the support available to you. Take your time.