Keywords for the e-commerce website are stuck at the bottom of the first page or on the second page

For a WordPress + WooCommerce eCommerce website, many category or product's keywords are currently ranking at the bottom of page 1 or on page 2 in Google search results.

If I fix technical SEO issues (such as adding noindex to filtered URLs like color, size, and model variations, and pagination pages), which was not previously modify).

improve internal linking between category pages and product pages (which was not previously optimized), and also build high-quality backlinks, will this effectively improve keyword rankings?

If yes, how long does it usually take to see noticeable ranking improvements?

In the age of AI there are many challenges. The things which you have mentioned are good technical things which will help with the page optimization. But there are also many things like domain authority, share of authority, good backlinks, mentions, citations which will help with your overall optimization.