It really depends on how you plan to use the telescope - deep sky, planetary, astrophotography, etc. Here’s a good guide to start with.

For what’s it worth, I’ve found an 8 inch Dobsonian to be the sweet spot between price, capability, and ease of use.

EDIT: if it’s not clear the word ‘Here’s’ in my comment above is a link to an article. I thought it would underline or something.