Куда бы мы ни ехали, нам всегда хочется найти тихое место, где хорошо работается и отдыхается.

Literally, Куда бы мы ни ехали is:

• куда – where (to)
• бы – particle that helps form a subjunctive / hypothetical mood
• мы – we
• ни – an emphasizing particle, roughly “ever / no matter”
• ехали – (we) went / were going (past tense of ехать, “to go by vehicle”)

So very literally: “Where (to) we would not go (by vehicle)”.

Natural English translation: “Wherever we go (by car / by transport)” or “No matter where we go”.

In Russian, the “subjunctive” or hypothetical meaning is usually formed by:

• past tense of the verb
• plus the particle бы

This doesn’t indicate real past time; it indicates an unreal / hypothetical or general condition.

So мы ехали by itself = “we were going / we went”.
But мы бы ехали = “we would go / we would be going”.

In constructions like куда бы мы ни ехали, the past tense + бы gives a meaning like “wherever we may go / wherever we go”, not specifically in the past. It’s more about the mood than about time.