I don’t mean/want/wish to boast/brag, but...

boast　ボｳ ｽﾄ v)自慢する

brag　ﾌﾞラｧｪ ｸﾞ v)自慢する

I don't mean to boast/brag, but... 自慢するわけではないけど、、 

I don’t mean to boast, but I traveled more than 20 countries and regions.

I don't mean to brag, but my kid and I won the race of family pair marathons.