I have direct TV and also Wifi if I stop my directv subscription but keep my wifi am I still able to have Roku
DirecTV is not needed in order to use your Roku.
BUT...
Any of the stations that you needed to authenticate with your "TV provider" credentials will no longer work when your DirecTV email and password are no longer recognized.
Cable-type channels want to be paid. When you have a paid subscription to a "tv provider" service that carries these channels (like your DirecTV subscription), they receive their pay out of the subscription fees you pay that provider. When you don't have a subscription to such a provider you are not paying for those channels.
Many cable-type channels make their content available for streaming via a "TV Everywhere" channel app for those paying for the channel through a provider as mentioned above. That service doesn't have to be a bloated cable or satellite service however. There are several services you can subscribe to and run on a Roku that may carry the channels you are interested in at a lower cost than you are paying now. Ones that come to mind to check out for any particular channel would include:
• Hulu plus Live TV
• Sling
• philo
• Directv Stream (the new name for the former AT&T TV)
• YouTube TV (which is currently accessed through the ordinary YouTube app on Roku)
• frndly
• fubu
• vidgo
... there may be others.
There are several places on the net where you can look up which streaming providers carry a particular channel of interest. Here are several such pages:
• https://thestreamable.com/channels
• https://www.groundedreason.com/cord-cutting/tv-streaming/how-to-stream-by-channel/
• https://suppose.tv/ (thanks to @DBDukes for this one)
• .. and again, there may be others
Savings in cord cutting usually come from picking and choosing which of the offerings you wish to pay for instead of paying for full blown cable or satellite services with scores of channels you never watch.