Changing main nav structure, titles, and links without hurting (maybe helping) SEO

[hstb]

I can't say our structure has changed but the products we want to put front and center as well as the categories/collections we want to highlight have changed. Before I go and just change our main nav's content and structure, what are some considerations for how to do this without hurting and hopefully helping SEO?

The new nav will make more sense to the customers so that's a plus. Is making sure the old links redirect appropriately enough? If not, what else do I need to do? I should also mention that we're going from a 3-level nav with approximately 200 links to a 2-level nav with approximately 100 links. So some of the old links will not be able to be pointed to by the new nav.

[KetanKumar]

@hstb 

sorry for that issue can you please share more details and store url

[hstb]

Please see above.

[KetanKumar]

@hstb 

sorry but it not clear