Wildlife Photography and camaras

Im going on Holiday on the 10th July and on Saturday me and Dad are going to be decideing what camara I’m gong to get  on Amazon to get it delivered in time for the holiday 

I still havnt decided on a model cause there’s so many and one model seems to have different say bursts per second, iso levels etc to another.

Iv used camaras since I was 12 so have lots of experience in photography but have never used DSLRs or Mirrorless camaras before so don’t know what there like in Wildlife Photography so I thought I’d ask what peoples experiences are in Wildlife Photography in DSLR and Mirrorless in both  full frame and crop factor Nikon and Canon camaras 

 What are anyones exspeariances with certain Canon and Nikon camaras in Wildlife Photography like  speed, burst rate, battery life and other important factors?