" I have been trying to plot bar with different colors"
For newer releases, this is fairly straightforward (demo) but for r2016a you can make a diagonal matrix with a stacked bar chart so that every bar is editable.
figure();
y2 = [64.5, 54.6, 44.7, 24.8, 52.2, 6.6, 3.2, 5.2, 52.4, 5.1];
bh = bar(1:numel(y2),diag(y2),'stacked','FaceColor', 'c'); %specify default color
% Set specific colors
bh(1).FaceColor = 'r'; %bar 1
bh(2).FaceColor = 'b'; %bar 2....
"I'd also like to plot yaxis with numbers and add names in the x-axis"
Not sure what you mean here. Numbers are already present on the y axis by default. To add names in the x axis,
set(gca,'XTick', 1:numel(y2),'XTickLabel',{'one','two','three','pi','four','five','foo','bar','ali','done'})
