In reply to geth21:
I can't get your first link to work but I'm guessing you mean these...
https://www.decathlon.co.uk/rock-climbing-id_8230651.html
If so I'd definitely recommend them, provided they fit your feet. I've got a pair and think they're great, very cheap, impossible to wear out and you can actually climb hard routes in them. They're not as good as top end shoes but in my experience the difference is small.
I personally wouldn't recommend the blue birds but they may work for you. The blue ClimbX ones from gooutdoors are better in my opinion.
Rember to get the fit snug but not uncomfortable and you're good to go.