Watch your local craigslist or facebook marketplace. With a little patience, you will probably find a good 8" or 10" dobsonian at a great price. I picked up a lovely 8" dob for less than $200. Most of the generic 8" F/6 dobsonians seem pretty decent.

Or check your local library. It may have a smaller Starblast table-top dobsonian you can check out - I did that when traveling once.

Whatever you do, do NOT buy a small cheap refractor on some flimsy mount. They are mostly awful.

If you want to commit to a build, this one is thought to be user-friendly and a great first instrument : https://www.printables.com/model/1325533-smallest-telescope-...

There are a lot of DIY telescopes out there. I suggest you spend several days reading about what others have done (and why). Start with an easy build to prove you can - people who get something small done are much more likely to finish a larger telescope, so start small as a practice run.