Can you? Sure.
Should you? In my opinion, no.
There's a lot of ethical problems around AI and you should really research it's impact enviromental etc (Spoiler: it is very bad). Even if you wouldn't be paying anyone cuz you couldn't afford it and therefore not taking potential money away from a working artist, it's still kinda sketchy ethically. The more people use generative AI even for little things, the more big corporations will continue to invest in it on all levels and take away creative jobs that they think they can fill with AI to "save money."
Also, generative AI/AI art is extremely taboo with a lot of people right now, because of above reasons. I'm not saying that you won't find people that won't care if you use AI, whether generative or just to enhance it, but there are going to be a lot of both readers and artists that will either not support you or actively shame you (not saying they should, just saying they will) for using AI in anyway. You could argue you that it's not the same because you're drawing the original image, but idk if people will see it as that big of a difference since you're still supporting/using AI. I've never used AI, so idk if you would be able to shake the stigma of AI artist if you stop using it.
I'm not an expert with it so perhaps you could still get big with it either way, but to me, it seems like an easily avoidable way to turn off a good chunk of potential readers when you could easily just wait until you save enough for a tablet. Seems a bit like shooting yourself in the foot.
Also, there are software programs that let you scan and upload handdrawn line work to it so you can color over it on your computer. Not quite as easy as having a tablet, but still an alternative. I think CSP let you do this, but I'm not sure since I never use it.
Also also, Idk what kind of tablet you are thinking of getting, but I know drawing tablets and ipads are expensive, but they also aren't the only option. I draw on a Samsung Galaxy S7+ and all the drawing apps work just fine on it and it cost me only $250-$300 after shipping. That way cheaper than the drawing tablets that costs anywhere from $500-$1000+. It doesn't have all the fancy shortcuts that the drawing specific tablets have, but honestly didn't mind since going from paper to digital drawing can be a bit of a learning curve and simplier is better. (I will note that the Samsung Galaxy tablets seem to have a dead spot on the right side of the screen I think for right handed people to rest their hand against the screen without the screen registering it as being touched, but it is pretty easily avoidable and there's still plenty of drawing space that I don't notice it really).
I think your better options would be either to 1) post your hand drawn comics and then redo them after you get your tablet or 2) just wait until you get your tablet and start posting them. I mean, what's the rush? It's not like you have to meet a deadline or you get fired lol.
Try switching to markers instead of using colored pencils. Colored pencils are notoriously hard to do well with out getting the grainy look (there's a way to do it, there's just a learning curve) and markers are way easier to fill large areas of color. I believe that's is what they used to use before digital software, but don't quote me on that. I don't mean the crayola markers, those also have a streaky-look unless you overuse them, but if you go to an art store, they have professional grade markers. Copics is the best brand, but also a complete set is pretty expensive even if it is less than a tablet. There are other good brands though that are a bit cheaper. I would just do some research on if water-based vs alcohol-based would be better for what you want, but I think if you try it out, you'll be way happier with the quality of your art.
At the very least, if you do decide to use AI enhancement, make sure you're upfront and label it as AI enhanced. People hate feeling like they've been tricked or lied to, even if they are okay with AI. Best to be honest and just accepted you're going to lose readers/followers for using it than to build up and audience and have them find out cuz they will not respond well to that.
Hope the info helps!