I did "petting" with my boyfriend I was on him naked and he had his boxer on but a bit wet of prejaculatory liquid he didn orgasm can I be preganant?

Very unlikely. Semen needs to get at least to the vagina for any chance of pregnancy. If you don't want to get pregnant now, use condoms every single time.
No way pregnant. Semen containing sperm must actually be implanted into vagina for pregnancy to occur. Pre-cum may contain sperm, hence withdrawing penis before semen ejaculation is the most unreliable form of birth control. Bot of ejaculatory fluid soaking thru boxers may make your skin damp or even sticky, but nothing else.