What should i do now?

I have had a friend like this. We got into a stupid argument also and ignored each other for weeks too. Sometimes it's better to be the bigger person and approach them. Whether it's through a letter, Face-to-Face or texting. Let them know in a kind way what you think about you two not being friends. Tell them how much you miss going on walks or doing things together. I'm not telling you to suck up to this person but it's better to talk things through. Let them know that you two don't have to be friends if they don't want to but it would be nice since you miss it.