Resources to help talk around conversations, especially for when you don’t know

Hello everyone,

I'm trying to find a nice guide/resource/article to help jumpstart some of the nuances when I'm having a conversation. I've recently been practicing and I realize I need the tools to explain myself so I can stop resorting to english to ask how to phrase something or what the meaning is.

Unfortunately most of the resources when I tried to look are really basic like 知らない/わからない or
Xという意味です and other variants and are either too short or lacking further detail.

I'm hoping there's a better resource(s) out there to help with this that people recommend.

I'm also looking for any brief guides on the words between sentences while you think. I KNOW there's a word for it in Japanese but it's alluding me at this point.

Thanks!