So for example on the tactics page after you've finished solving, if you click on the blue circle under the move list you'll see a bunch of icons.
The second method is to launch the play vs computer from the blue circle menu shown below most move lists on the site. If you click on a bot name you can also challenge them directly to a time control of your choosing, and you can play unrated which gives you the option of choosing the start position. You can also see the bot usernames on the user list page. On the challenge panel you can toggle bot challenges on to see their challenges in the challenge filter (click on the filter icon in the top left of the challenge panel). The bots are the usernames with a little computer icon next to them, and they all start with a capital letter in their name that signifies difficulty (H = hard, M = medium, E = easy).
One is to play against bots in the playing interface. There are three methods of 'play vs computer'.
