Should I let it go?

To be honest, I think you’re right in that he is comfortable with how things are and doesn’t want things to change. It really concerns me that it turns into a fight when you try and discuss the future - you’re absolutely within your rights to discuss what you want out of life! If you really want children, marriage, a house etc and he won’t even discuss those things, you would, sadly, be better off letting him go.
He either genuinely doesn’t know what he wants, and gets flustered when you bring the future up, or he’s cruising, stringing you along. Either way, it’s really not fair on you. I’m really sorry he’s being like this, though. It’s so hard when you love someone and they’re not willing to even meet you halfway.

It just really sucks... because my family will ask in casual conversation ya know? And I never have answers... or I just look stupid... and then when we try to talk. Its like he hasnt thought that far ahead or something. I’ve seen people go and stay together for 10+yrs and have not changed their relationship or living situation in anyway shape or form. And that works for some people! But idk.. when siblings and friends are all married and starting families and here we are just crammed in an apt living through the motions... it gets depressing...even now.. hed rather spend the day playing videogames instead of coming to me and saying “ ya know Ive thought about what you said and __________” something ya know? But no.... he seen me this am and asked about going for a walk again.... not an apology... not an answer to anything I asked him....
Or it’s like he thinks if he gives me simple things now, ill forget or idk itll be enough for me to drop it. Like a child , you give them a toy to distract them from somewhere they want to go or something else they want but cant have. He thinks if he buys me small knick knacks or whatever itll make me more accepting of staying here. That itll make me more comfortable......

Tick-tock....the sound of the clock ticking seconds, minutes, hours of your life away.

He's wasting your time. Stop waiting. Get out there and find someone who is ready and live your life with that person.

You can't fit a square peg into a round hole and you can't make someone who's content to be single and not tied down want to become legally and financially entangled with another person.

Free yourself.