Jealousy Problem ‼️🤔

I'm very insecure about myself,and I'm very jealous and possessive with my boyfriend,we been together for a year and 3 months && I love him very much. We work together and we have the same shift,so we see eachother everyday ALL day. There are some girls that I've seen that look at him,or smile and I get very jealous 😩he doesn't talk to them,but I take it out on him for everything that they do(I feel bad) . How can I control my jealousy towards him and be more confident within myself and our relationship .... I need soon advice this drives me crazy 🙄😪