How can i insert a big table in IEEE template?

You need to use a table* environment instead of a table environment, to allow the float to take up the space of both columns.

In addition, you need to do something to reduce the width of the table. I suggest you use a tabularx environment instead of the tabular environment and that you use a centered version of the X column type for columns 2 thru 11. Use an l column type for the first column and a c column type for the final column. (If you really want to left-align all cell contents, use the X column type for columns 2 thru 11.)

Oh, and to try to give your table a more "open" look, say, by getting rid of all vertical lines and most horizontal lines and by generating well-spaced horizontal rules with the help of the booktabs package.

documentclass[conference]{IEEEtran}
usepackage{tabularx,booktabs}
newcolumntype{C}{>{centeringarraybackslash}X} % centered version of "X" type
setlength{extrarowheight}{1pt}
usepackage{lipsum}
begin{document}
lipsum[1] % filler text
begin{table*}
 caption{CIFAR-10 Confusion Matrix}
label{my-label}
begin{tabularx}{textwidth}{@{}l*{10}{C}c@{}}
toprule
labels     & airplane & automobile & bird & cat & deer & dog & frog & horse & ship & truck & accuracy  
midrule
airplane   & 915      & 4          & 17   & 19  & 3    & 1   & 0    & 2     & 27   & 12    & 91.50%   
automobile & 8        & 934        & 3    & 4   & 0    & 0   & 3    & 0     & 10   & 38    & 93.40%   
bird       & 60       & 1          & 813  & 37  & 19   & 23  & 30   & 10    & 7    & 0     & 81.30%   
cat        & 18       & 1          & 34   & 746 & 25   & 113 & 37   & 18    & 8    & 0     & 74.60%   
deer       & 24       & 1          & 38   & 33  & 809  & 19  & 44   & 29    & 2    & 1     & 80.90%   
addlinespace
dog        & 4        & 0          & 37   & 106 & 23   & 792 & 9    & 26    & 2    & 1     & 79.20%   
frog       & 2        & 5          & 19   & 35  & 1    & 20  & 912  & 2     & 3    & 1     & 91.20%   
horse      & 14       & 0          & 26   & 20  & 18   & 28  & 4    & 886   & 3    & 1     & 88.60%   
ship       & 35       & 10         & 3    & 2   & 0    & 2   & 1    & 0     & 936  & 11    & 93.60%   
truck      & 23       & 37         & 4    & 10  & 1    & 2   & 2    & 0     & 15   & 906   & 90.60%   
bottomrule
end{tabularx}
end{table*}
lipsum[2-15] % more filler text
end{document}