How many times a day should I walk my dog?

Last time I did was a couple weeks ago. Not to long ago. I know I get busy with my life but I feel awful for not walking him. I play with him a couple times. My oldee foster brother asked me why don't I ever walk him. I told him I do but it's been a couple weeks. Last time, people said I should be a shamed of myself for not walking him. At least I feed him and give hin toys. I admit. I haven't been doing the best job and I already feel bad. I love my dog more than anything. Please no hostile comments or mean comments about this. I already feel bad about it already. How many time a day or how many days I week should I walk my dog? Thank you.