Yes you can. Whatever war date we are at ,is where you would start. Right now we have 2 waves. first wave launched yesterday. 2nd wave will launch in 1-2 weeks. Also we are playing 1 war day for 1 real day. However that will increase to 2 to 1 soon. So you have some time. If you get your computer fixed quick enough you may be able to join the 2nd wave.
seeya soon