Ovulation with irregular period

Hi everyone,

I have irregular period of 3-6 days late generally , last 4 months i am trying to conceive but not getting pregnant.

I had my last period on 16dec 2021 then ovulated on day 29 (14jan ) and this month i have my periods on 9 feb2022, for me i have never this much gap between periods ..so i have too many questions in my mind like something is wrong with my body that i should know.....

1) with irregular periods will i ovulate on same day in upcoming cycle?

2) is there any tips for ttc with irregular periods?

3) do i need to make sure of any other things? Like food intake or exercise

4) i heard from some people say that when you try to conceive you need to make sure not to do exercise, fast walking / not to use stairs, .......etc

Is it true???

Thanks in advance!